It’s possible that there are some issues here, but the fact that these comments talk about a wide variety of laptop models with completely different screens, form factors, manufacturing processes, etc, suggests that there may not be a systematic issue.
One model having the issue would suggest a manufacturing issue. However it’s unlikely that completely different models all exhibit the same issue in the same way.
More likely, screen damage is a common form of accidental damage, and anyone googling for support will find threads like this and pile on with their own experience despite no actual link.
But having said that Apple would never admit to such a widespread fault even if it did plague their laptops. I fondly remember the 2015 A1502 trackpad cable failure where the keyboard and trackpad fail because of a deteriorated cable. It's a well known issue, but Apple just refused to acknowledge fault.
Took them forever to admit that their butterfly keyboards were faulty too.
Having said that, this apple discussion forum is probably a terrible way to organise around a supposed model being prone to screen cracking. The quality of the reports are bad. Also for every reported m1 air that has a screen crack, it would be nice to see pictures so a pattern -- if one exists -- could be identified.
One model having the issue would suggest a manufacturing issue. However it’s unlikely that completely different models all exhibit the same issue in the same way.
More likely, screen damage is a common form of accidental damage, and anyone googling for support will find threads like this and pile on with their own experience despite no actual link.