Modern filesystems can corrupt as well with unclean shutdown. They are just less likely to do so.

It shouldn't be possible for them to become corrupt on an unclean shutdown, at all. Not at the filesystem level. It isn't just a question of probability.

It's possible that there is some bug in the implementation of a filesystem that causes it to violate its guarantees.

There could be, oh...hardware bugs, say, where hardware violates guarantees.

Files can be partially-written. Software might not handle that, though properly-written software designed like a DBMS will be set up so that a partially-written file will not become corrupt at the file level.

Some filesystems permit disabling features that guard against filesystem corruption.

But absent something like that, it should not be possible for one of the filesystems to become corrupt on an unclean shutdown, at all.