Reposting a comment I made somewhere else on the site cause people are finding it useful.
Im not a mod, but on a smaller scale on my own profile, I grabbed all my most upvoted comments (started from the really upvoted ones until I reached 20 upvotes or so) and edited them out to only leave the first few phrases or words. Then inserted a message that read:
"This used to be a full comment, you can find more resources in the link bellow since I have moved to kbin and reddit doesn't deserve my content! Bye reddit, you won't be missed!
For more [subject] advice, find me on https://kbin.social/m/[subject]"
Bonus points if I could cut the comment out at the exact time it was about to become useful "Whats actually going on here is that..."
Did that sorting by most upvoted and also my fresh, since it wass manual I only managed to do so much, But I liked the approach better than just deleting it all or editing with "fuckspez" so that they could get back and revert it.
May not be the solution for everyone, but if you made and posted some important self-made content on reddit (say a guide of some sort, a compendium of usefull resources, etc), editing it out like that could work to keep it gone and redirect trafic to the fediverse.
Since its manual you can't do it for all content, but you could do it to anything important you built in that community.