That’s a good question, and I think the best answer is that I’ve had the most experience on the 5.13 kernel. I recalled there being amdgpu errors in the early 5.14 kernels, so I ended up waiting until 5.14.10 before I updated my kernel, and then there wasn’t another released until the last stable release which also brought 5.15.2 LTS, so I thought I’d try that.
It’s just drive space, so I’ll probably install the 5.14 kernel too 
I think my issue lays somewhere between (a) why did VLC sleep the monitors in the first place and (b) the bug post I found concerning failed resumes. I think sleep mixed with video rendering and screen wake-up was a recipe for disaster.
I think tomorrow I’ll try play the video again after I push out my monitor sleep time to 2 hours to see what happens. Although, my monitor sleep time is set for 2 minutes, so not sure why 10+ minutes into the video is when I noticed the blanking. 
fun with kernels…
