On both 6.16 and 6.15.8 I get the same behavior as usual. It “works” except for the completely unacceptable bugs described above.
It does work flawlessly in mpv-full-git and clapper.
My chromium-flags.conf
--enable-features=AcceleratedVideoDecoder,AcceleratedVideoDecodeLinuxGL,AcceleratedVideoDecodeLinuxZeroCopyGL
and “Preferred Ozone platform” is set to auto in chrome://flags. No other env variables.
I have this https://github.com/edk2-porting/edk2-rk3588 on SPI flash, so maybe it is a UEFI vs uboot thing.