Let me throw in my three cents.
This reads like a personal speculation of podcast author.
While a medium stealth bomber might be in consideration at an analytical or conceptual stage it is (1) extremely unlikely to result in a prototype because it would be a (2) bad procurement decision by PLAAF. Claim (2) is based on historical evidence and available data while claim (1) is based on my observation of PLA procurement strategy which I view as more rational and economy-driven than Soviet procurement.
Explanation of (2):
- Tu-22M3M is a modernization of an existing asset (Tu-22M3) to prolong its service by 10 years to fill the gap before Tu-160M2 is available in sufficient numbers and to improve the economy of production of Tu-160M2 as it unifies engines (NK-32-02) and avionics.
- Tu-22M3 was the second main production "block" of Backfire produced between 1983 and 1993. It had new avionics, improved engines (NK-25) which increased fuel efficiency, range and top speed (2Ma from 1,6Ma) and a rotary launcher for Kh-15 missiles which improved flight performance. It was the variant which delivered performance that Tu-22M was intended to have at concept stage.
- Tu-22M2 was the first main production "block" of Backfire produced between 1972 and 1983. It was rushed into production with weaker engines engines (NK-22) which were replaced by improved ones (NK-23) on some aircraft.
- Tu-22M was proposed in 1960s as modernization of Tu-22 despite being a new design as a cheaper alternative to the expensive 3Ma bomber proposal by Sukhoi (T-4). Soviet Air Force backed Tupolev out of fear that high cost of T-4 program and poor performance of existing bombers, and especially of Tu-22, would shift even more resources to Strategic Missile Troops because Soviet planning and economy failed to deliver a viable bomber force missiles were seen as both more effective and economical.
In theory Tu-22M replaced the Tu-22 which
replaced Tu-16. In practice because both Tu-22 and Tu-22M2 were under-performing and expensive Tu-16 stayed in service until the end of Cold War and would likely be retained in service instead of Tu-22M
if its production wasn't ended in 1962.
Even by the standards of its era Tu-22M was a
jobs program and its history resembles the history of A-10 - an under-performing aircraft resulting from inter-service rivalry which is kept in service because of institutional inertia and lack of alternatives but which never performed its intended role.
Backfire ended up providing more useful service in Naval Aviation as a stand-off platform for the "Bastion" doctrine. In 1991 Naval Aviation had 130 Tu-22M, 125 Tu-16 and only 15 Tu-22 as well as 160 Tu-95 and only 15 Tu-160 with most M-4's being withdrawn from service. In 1991 Long Range Aviation of the Air Force had 190 Tu-22M, 120 Tu-22 and 80 Tu-16. Currently there are ~60 in service with 52 in combat units but only a maximum of 30 were slated for M3M upgrade, which is the approximate delivery capacity equivalent of 10 ordered Tu-160M2's if you ignore the range.
Americans developed B-1A in
the 1970s but Carter cancelled it because of cost overruns and insufficient performance. Reagan restarted it as B-1B as part of the military buildup but
at the time USAF openly recognized that S-300 and MiG-31 made B-1B obsolete. B-1B was produced between 1984 and 1988 with a
expected lifespan of about 10 years by which time it was meant to be replaced by ATB (B-2). It was not rational planning but Reaganomics. Afterwards B-1 stayed in service and repeated the case of A-10 while suffering from low readiness and technical issues. It is prioritized for retirement before B-2 while B-52 is being modernized and will likely outlive both.
There is no reason to invest resources into an under-performing platform. USA built 100 Tu-160 near-equivalents while USSR built 300 Tu-22M2's because of economic and technological limitations. But in the end
both proved to be economically inefficient and tactically obsolete middle-ground between high-end bombers (Tu-160, B-2) and economy bombers (Tu-95, B-52).
You base your concept on paper stats and theoretical calculations of range and flight time while actual war planning should be based on logistics and sustainment of operations. Case in point: Russian invasion of Ukraine.
Combat aircraft are machines which operate in extreme conditions as soon as they leave the hangar. They wear out extremely fast as well.
Maintaining one combat sortie per day over a period of several weeks is very difficult. Being able to achieve four sorties a day for the first two or three days of combat is
very easy. You just completely ruin your aircraft and crews in the process and end up unable to fight - something that is typically not simulated in computer wargames.
Conventional airstrikes - even massed ones - have limited destructive power. Rarely a well prepared target is destroyed in a single sortie. Two or more is statistically more probable and that involves a period of time to ascertain the damage. You don't perform an airstrike and then immediately follow up with another. You perform an airstrike, assess the situation and then restrike hoping that sufficient repair effort went into it that you destroyed additional resources. Ideally you restrike the target just before it becomes operational again thus ensuring that it's neutralized and that opponent wastes maximum resources. You let the opponent move repair crews to a struck target and tie them down then attack another target that won't have rescue/repair crews available.
Actual bombing campaigns are not conducted like "Shock and awe" in 2003 which was
a psychological operation and a propaganda stunt but like Desert Storm in 1991 which was
five weeks of consistently high sortie rates. No combat scenario that China should consider - including Taiwan - is a "Shock and awe" scenario. Actually I don't imagine any of them as a Desert Storm scenario either - that was too comfortable.
All combat is about position. Fire enables maneuver by suppressing the opponent and the maneuver forces the opponent to change position to a less favourable one. Ground, air, sea even information/cyber - it's all the same. You either remove the enemy from position by overwhelming force (requires multiple heavy bombers) or suppress him by consistent pressure (requires multiple sorties over long period of time). This has been true since ancient times. Either overwhelming force to break the defense of most efficient erosion of defenses. The middle ground doesn't really exist because it's not good at either of those allowing the opponent to use both.
If we use Kh-55 as reference then a cruise missile is 6m long, 0,5 wide and weighs 1,6-2t. A Su-34 size plane can fit at maximum four of them internally. If we optimize the design of both plane and missile it might be increased to 6. That gives us 8-12 missile volley with 2 planes and 16-24 missile volleys with 4 planes (and let's not forget that maximum payload means minimum range). Beyond that a heavy bomber is more economical.
Ohio SSGNs have 168 Tomahawks and Virginia Payload Module has 28 to provide temporary filler until "Large Payload Submarine" is available. Shayrat base airstrike took 60 Tomahawks. Maritime strike has similar limitations if you consider the number of defensive missiles and possibly additional unmanned platforms for screening.
Even a scramjet hypersonic missile is better launched with a booster or from a combat drone than an expensive manned plane. It makes economic sense to develop such drones and then send them on combat missions as "loyal wingmen" to "command node" aircraft like the J-20 twin-seater. That allows the manned aircraft to perform C2 and air-to-air while drones perform air-to-ground. Bomber and escort is the ideal combination.
Production-wise there's no reason to develop a stealthy Su-34 because it will conflict with more rational production of a stealthy Su-30/35. Diverting resources for no real gain is
a loss. China is catching up so it can't afford a loss.