after a lengthy phone call, apple said bring it in for apple store support.

apple checked the machine and the next day told me it would cost $750 to repair.

this is not an isolated incident and relegated to 26.4.1:

https://www.reddit.com/r/mac/comments/1snmllz/tahoe_264_bricked_my_m2_macbook_pro_apple_quoted/

https://www.reddit.com/r/macbookpro/comments/1skw0xd/quick_fix_macos_tahoe_264_2641_killed_my_macbook/

fixes explained in those posts did work, but ended up having to wipe my machine. what the hell is going on?