Once upon a time I thought the same thing. 10bit files plays horribly and 8bit files are fine. Yet the HVEC decoder by Microsoft changed my mind.
If you keep using Directshow to play videos, 10bit VR videos will suffer. Only HEVC decoder can save the day. However, even today I still don't know the mechanism of HVEC filter. Like Jensen Huang said, "it just works".
However, when it comes to AMD, the HVEC just don't want to work, hence your dilemma.