I'm sorry to intrude, but is this specific to Raspberry or is it for all architectures?
I'm into buying N100 based motherboard, and I'd like to have HW accelerated decoding of h264, h265 and AV1, which is supported by that iGPU. Should I postpone it?
I believe this discussion is specific to the Pi2/3 HEVC implementation. That platform doesn't have VPU (video processing unit) support for hardware acceleration of HEVC/h.265 but instead uses a combination of CPU and GPU compute (not the same as dedicated VPU support) to allow HEVC content to be played on a platform that otherwise wouldn't be able to.
The Pi 4 and Pi 5 both have hardware HEVC/h.265 VPU blocks to allow for hardware acceleration - which is supported in newer versions of LE.
Other platforms like x86 which have 'GPU hardware decode' (which is more like VPU decode on ARM platforms) of HEVC are a different matter and depend on the driver support for that platform. I'd expect recent Intel CPUs to work fine once driver support for newer processors has made its way into the code base.