In order for them to get in trouble over that your comments need to contain personal information or hints to identify you.
I'm considering dropping some hints and minor personal information in comments, then requesting a GDPR wipe and if they're still there after thirty days sue then for GDPR violation.
If they'd need to delete all comments of leavers Reddit would be such an empty place.
Yep, they've restored mine twice now. It's important to not delete your Reddit account because they aren't restoring those. If you want to nuke your comments, you have to keep your account open so you can keep deleting them. If nothing else, make them pay server fees for this bullshit.
I overwrote each comment with "Fuck u/spez" before deleting them using PowerDeleteSuite. That way, if they were to restore my comments, it'd be autoremoved right away on most subs.
I've Power Delete Suite'd mine three times; ca. 500 the first time, 800 the 2nd (!) which was this morning, then I tried later, and only 81 the 3rd. Now my account "only" shows 9. Dunno how much overlap there is in all that.