Linus tech tips on YouTube did a video about a windows bug where sleeping while charging would allow the laptop to wake up to check for updates etc but often caused this issue of turning on in a bag
It wouldn't happen that this feature was released around early/mid 2020? Windows sleep used to be semi-reliable but one it's been shit for a couple of years.
Search "LTT Windows Modern Standby" on YouTube. Sadly all the workarounds to turn it off no longer work reliably. For reliable sleep, buy a Framework (only current Windows laptop that still supports S3 Sleep) or Macbook.
