This is very worrying, I had a similar issue with my MacBook Air, which died in about 4 hrs of getting it. On opening it last Saturday, I got it set up, installed Spotify, played a little music, did a bit of web browsing, then was about done with it for the time being and about to watch a movie, but saw there was a software update available so I clicked for that to install.
Started watching a movie, checked on the MacBook Air about half hour later to see it was off. Figured it perhaps just shutdown after the update and tried turning on and nothing. It was dead, not life at all, no lights at all to indicate life. Tried holding down the start button, etc. Finally run Apple support, they had me on the phone for about 40 mins, she didn’t fill me with confidence that she knew what she was doing, maybe these M1’s are too new. Anyway, she had me to try a bunch of reset options, but nothing brought it back to life and they after escalatino to someone more senior, was told nothing they could do remotely and to return it for a replacement.
So my MacBook Air lasted in total about 4hrs. ? In case anyone is wondering,it was about 70-80% charged on opening and then I had it plugged into the wall charger and was plugged in and charging when I did the update. As Apple suggested I returned it and I’m just awaiting the replacement which is due on Monday, but having just read all the comments on the Youtube clip linked on the first page of this thread, it’s clear others having issues (not necessarily massively widespread of course), but does have me half thinking I should have just got a refund and maybe waited for next year’s model.