So, I was getting hourly blackscreen crashes on 20.4.2, then less regular Video TDR Failure bluescreens while gaming on 20.5.1. After doing everything I could think to remedy it (DDU on drivers, fresh install, changing pcie gen, etc.), I tried a "it couldnt make it worse" fix and swapped from using DisplayPort to HDMI, and I havent had a crash in a full week now. Another person on overclock.net said it fixed it for them too.
Its not ideal because my Freesync range has gone from 40-144Hz to 40-100Hz, but not having the crashes is a breath of fresh air.
It would be interesting to see if this helps anyone else, and could potentially point to a problem with either their displayport drivers, or high refresh rate freesync. If it does help anyone, please post your monitor specs and GPU below!
My Specs: R7 3700X, Gigabyte Auros X570, Sapphire Nitro+ 5700X, 16GB 3600MHz RAM
Monitor: LG 27GL850, 1440p, 144Hz