3 points
You quoted those two sentences, but skipped the three sentences right before them:
BCM2712 supports HEVC 4K60 hardware decoding. It no longer supports H264 in hardware. This might sound odd but it removes the RPi4’s 1080p restriction on H264 decoding and the 4K H264 test media we have has played.
To my eyes this implies it works fine for 4K h264. The sentences you quote from are sort of a “furthermore, at 1080p it can handle these more complex codecs as well” to my initial reading.
I’m not saying you’re wrong, just explaining why I parsed this paragraph a bit differently.
