I just made myself moderator of a random subreddit. the API is still free for mods. also there's something you can do where you patch the boost for Reddit app using revanced but I'm not sure how that works
Surprisingly, it works. There are some minor errors, like the app not being able to open the new format of reddit post links, error 404 on profile page, many more
I still use it. Some things don't work right anymore, like posting single images (although multi image posts still work). As long as you are or have ever been a mod, it still works fairly well.