Sounds like something that could be solved in a friendly competition and live rounds. Replace the pilots with remote control. Create a 100KM hot zone and a 300KM TFR in some desert. Aircraft enters the hot zone and is marked a live enemy combatant. Both sides must broadcast live from all equipment involved.

Would they say… “we can’t “?

I wouldn’t expect that.

If they can or can’t in a given circumstance seems entirely unrelated to statements like that. Maybe they can, but even if they can’t I wouldn’t expect them to say that.

China says a lot of things.

I don't think the new heat seeking missile can hit an F-22, or that the new UHF radar can detect US stealth aircraft.

A once heard a pilot say something like, they can see me, but not well enough to hit me, but enough for my missiles to hit them.

That is to say detection is not enough to shoot down an advisory and it gives away the radar location.

With photogrammetric thermal imaging, what in gods name is radar needed for?

Radar has much longer range than IR. Heat seeking missiles are usually relatively close range weapons, i.e., less than 20 miles.

It’s not stated directly, but my read on this is the new UHF radars can detect an F22, but cannot track it precisely enough for a radar guided missile to hit. But, they can get a hypersonic missile to the general vicinity, at which point the IR seeker takes over.

China and Russia have had 30+ years to find countermeasures to American stealth jets so I would expect these weapons are at least somewhat effective.

I used to develop software for these missile defense systems and you are right, there is a big difference in the track quality required to successfully guide a missile into the path of an aircraft instead of just tracking the aircraft from miles away