Yes, many have come out and said that they simply won't be able to properly moderate once third party apps die.

Yep.

Hopefully a large amount of moderators and contributors keep staying away from Reddit, that'll drastically lower the quality of the site and thus their money making ability.

I'm definitely staying away.

People are great at getting used to things, just give it a few days and you'll have figured out the fediverse.

I don't think reddit will backtrack at all.