But renders of Tsirkon suggested a wedge shaped HCM shaped just like a X-51 and what Ukraine intercepted (or retrieved a detonated/faulty Tsirkon) was similar looking to a Hy-Fly or Ling Yun. All three are very closely looking. The American Hy-fly was the first of these three to be made known public. While that doesn't prove it came first, it does at least indicate this.
Nevertheless this sort of HCM is low tier level for Russia, China, USA. India does not yet have even experimental air breathing hypersonic speed cruise missiles in testing. China didn't even bother placing one of these Hy-fly like HCMs into service. Just played around with some testing. To be fair, the Americans also abandoned this as part of their previous Prompt Global Strike platform (they have higher sights and aims like the Chinese). Russia inducted the Tsirkon, let's call it Hy-flyski, no disrespect intended to Russians at all. It's fair to say China and Russia
were both behind the Americans in aerodynamics for a loooong time. This is much less the case today and possibly not even the case. One of those countries have made strides.
India has test fired scramjet engines for tens, possibly now at hundreds of seconds at ground test level. That's roughly a decade away from sustained propelled hypersonic live flight tests for HCM equivalent. That is impressive in its own right though and no other country is even on this ladder. Japan has talked a lot and South Korea has initiated some programs too.
My guess is China already has rotating detonation and/or oblique detonation propelled HCM in the works if not already in service. There is no chance China discloses this before they are already mature. The public only found out about the existence of DF-100 when PLA apparently stopped its production. We only found out about DF-17 a few years before DF-27 was leaked by US intelligence to be flying around as a dedicated anti-ship HGV.
Point is Avangard could be much less impressive than a wedge glider. Would not be surprised if it is indeed a double conical MaRV mounted onto ICBM ranged booster or even IRBM for flexbility of platform.
So far the US latest HGV tests - HTV2 and darpa's HAWC combined air-breathing glider both have been failing as far as they say. Only China has successfully fielded gliders as far as public domain information goes. This is admitted, indeed was initially made known to the public by the US itself, commenting on observing hundreds of successful glider flights (different flight profiles compared to HCMs and of course goes without saying, ballistic missile hypersonics). I don't think North Korea developed a wedge HGV on their own. They apparently have no hypersonic wind tunnels but admittedly probably do have access to Russian and/or Chinese ones. Then again a wedge glider isn't that out of reach either with guidance from someone who's already done a few.
A wedge shaped glider probably just improves aerodynamic lift and adds some range. It could even have constraints like slower speeds compared to double cone gliders. Just seems to the public as more advanced than double cone because double cone gliders have been in service in PLA in the form of DF-15, DF-21, and DF-26 for well over a decade. Does Avangard need to be wedge shaped glider to be an effective and threatening weapon? No.
Should add that the US LRHW is a double cone glider. Nothing too different to a DF-21 or DF-26.
Some public domain info on double cone glider: