many times you'll notice the new mod became active as a contributor on specific sub only 2-3 days before the OG mod gets banned and sub declared orphan.
Coincidence?
How can reddit even hand over a sub to someone who has nothing to do with a community? Simply because they install and control who controls the sub.
Mods get "comment/post removal" power, so they use it to shape the community towards specific "narrative", there is no audit trail for any mod specific actions unless you are a mod you perhaps can't see what all a mod is doing on a sub.
Also, they can simply make an automod/bot rule which simply removes your comment by creating a rule with your username after that you'll not know your comment is gone but others will not see it!