Disabling Thunderbolt-related kernel extensions in the SSV on Big Sur (Random Crashes 2015 Retina MacBook Pro)
Kudos to naguzmans on the macrumors forums with the answer.
https://forums.macrumors.com/threads/help-updated-to-macos-10-12-4-mbp-randomly-shuts-off.2039446/post-29236887