Sadly I have to agree. Ryzen 3400G here, getting hardware transcoding on the iGPU is something I still haven't sorted out. There have been several recent issues in kernel, AGESA firmware (I suspect there might be newer versions with potential fixes that my mobo manufacturer hasn't released yet; this is 1.0.0.4 Patch B) and drivers. I've had several rounds of hunting down and compiling various versions of driver packages, modules and kernels from source, trying third-party PPAs, to no avail. The amdgpu/amdgpupro mess adds another layer of confusion.

I am not sure if I am missing some update, need to set some undocumented kernel flag and/or BIOS setting, if it's a software issue or Í just made a mistake somewhere. Debian 10/11.

Meanwhile, as much as I wanted to get away from Intel, their drivers have never posed any issue at all.