That won’t go well.

If you’re investing in paid moderation, you don’t want different mod teams moderating different subreddits - that would be a waste of money, and a pain to coordinate. Instead you want to gather the whole “Reddit mod team” as a single unit, and give them a single set of rules to enforce over the whole site, across multiple subreddits.

In other words, it makes no difference if you’re in a small and specialised subreddit or a large and generic one. Say hello to people posting memes in discussion subreddits, rhetorical questions in “ask” subs, so goes on.

And since now subreddits are more similar to each other, there’s less of a point to stay in the smaller subreddits. People will congregate even harder into the larger ones, that are way harder to moderate than the smaller ones (more users = more activity, conflict, and trolls per user). This might create a paradox, where more moderation will cause lower enforcement of the rules, since users are breaking them more often.

The same applies if they’re investing in automatic moderation. With an additional issue - it’s easier to exploit it.