If there's a detailed argument saying that basic moderation (eg. obvious spam removal and not "I want to ban everyone who's ever said anything nice about Trump") will take say an order of magnitude more human effort without 3rd party tools I'd be curious to see it. If there's a persuasive claim along these lines I'd shift my beliefs, but I haven't seen it so far.
https://github.com/toolbox-team/reddit-moderator-toolbox
I don't know if the proposed API changes will affect this specific tool, but I doubt moderators would be nearly as up in arms if their tools were going to keep working the way they had in the past.