So I have this issue as well, but specifically when loading into Overwatch 2 matches.
https://clips.twitch.tv/SilkyZealousJamSoBayed-GfbfdQgkPRIwSISZ
So far, I've lowered the frame rate to 30, and I tried resizing it to only the size of the avatar. While it is not this extreme, or lasts this long, it still blows up.