My reading is su-57 was
never planned as penetrator strike aircraft, or even OFCA. Thus - when in offensive role, there is very high attention to stand off munitions (LACM, loitering munitions, glide bombs, VLRAAM - almost no internal stand in direct attack weapons!), no internal EOTS (targeting pod for safe scenarios only). Moderate defensive stealth.
Penetrator role is expensive, high risk/high reward task, and sending few available 5th gen aircraft (or any aircraft) into blue airspace, against much larger air order of battle, was probably seen as waste of a very limited, irreplaceable force resource.
Another detail here - Russia earlier than most others added S-70 into the equation.
I.e. it's a specialized DEFCA "hunter" in hunter-killer teams (with su-35s and their powerful radars), aimed to close emerging gaps for IADS v. stealth intrusion (F-35). I.e. it's a specialist force multiplier versus NATO, aimed to deny it its greatest strength.
Just as Su-35s was aimed, to a large degree, to tie down few available raptors under GCI guidance (not fight them equally, just deny them one-sided high altitude dominance over red airspace), together with (mostly) S-400s. Threat evolved (F-35 force numbering thousands), so the shield had to evolve, too.
Su-57 stealth is good enough to outrange detection by intruding blue VLO strike fighters x- band sets (via L band) in favourable conditions (LPI mode) over friendly territory. In a much wider deg sector (270 deg v 120 deg) than them, while simultaneously guiding 4++ gen killers(same su-35 with bruteforce irbis sets) to attack identified targets.
If things went wrong and it got caught anyway - powerful, 360 deg broadband EW, IR jamming and goot kinematic/maneuvering performance to get out.
At the same time - superior range and range:speed performance, esp. for strategic maneuver (enough range to cross Russia from side to side in one flight).
Notably, per silentflanker simulations, Su-57 does quite well v. 4...1.5 ghz, i.e. versus AWACS planes working from extended ranges. And this is one of more believable notions - in lower bands, much of criticism against his models is much less valid. And, unlike others, Su-57 also jams S/L band, too. Just to be sure.
TLDR: Very Russian need v. NATO, and indeed it's kind of super rafale in all imaginable ways.
Problem is selling such a tailor made aircraft - expensive aircraft - to others. And here it's kind of cought into su-35s trap - it's multirole and viable, but it isn't really great at performance metrics market expects.
India, ideally, needs a very normal aircraft. Their main opponent is Pakistan, Pakistan isn't a nation India needs to desperately defend against. they want to do Israeli things to them. Su-57 isn't delivering that.
China is a better sell for this capability, but i never saw any Indian calculations for full on Chinese aerial/ground offensive right through Himalayas (one wonders why). And in any case, to make it viable, su-57 is a tip of the spear. You must heavily invest into IADS first.
As such, for IAF it's a bit of mixed bag - better Rafale is very attractive to have, but they are fully commited to a normal one already, including basing domestic aircraft off its technology. And now IAF is in a limbo - Rafale itself is like an Oak tree - it's french weapon ecosystem is very incompatible with anything non-french, and slowly kills anything around; israeli towed decoy is a very telling story.
From this PoV, Su-57 delays meant it came just too late - and its tech/tech transfer isn't exactly magical over well developed and already integrated rafale.
At the same time, IAF
really needs just a goddamn better plane, ASAP. 2024-25 was non-stop series of shocks for them urgently telling that and just that. Add in powerful lobbies, very vocal indian politics and external pressures, and it is not a nice position for a humble bureaucrat to be in.
Plus SU-57 carries the R-37M with an alleged BVR range of 400 kms.
It does, but only external and only as backwards compatibility feature. Ultimately it's a previous gen weapon from 2010s. Su-57 has its own VLRAAM, known as article 810, which is both more ambitious and fits inside.
ToT may still be an issue. The original deal for the SU-57 collapsed partly because of that, tho I would imagine the Russians will be more accommodating this time round.
It was some sort of excuse negitiation at that point.
Indians were very unsatisfied with su-57 stealth performance, delays and risks (especially after famous engine flameout during demonstration, which was probably supposed to show that program is going forward). At the same time, Indians really, really needed aircraft in original timeframe (not like IAF were blind during Balakot strikes that they're one weapon generation behind Pakistan); Su-57 looked like a failed bet.
Russia was already not willing to make a separate, very different Indian version out of its own pocket, and ToT requirement for miniscule indian investment into that program was outright laughable (IAF isn't getting anything from French for much older and inferior aircraft, for many times the money...they aren't even getting proper system integrations).
Perfect storm. Now position may be way more convergent - Russia appears to work on double seater; if India wants one with Uttam (no one knows how the hell indians wants to integrate it with rest of Byelka - probably same way as X-guard) - it's their right.
