The boost dev in his whinge post about the new costs said that his revenue was in the millions of dollars a year. His costs are……his time. There’s no way the other devs for apps like sync and RiF also didn’t make millions.
Also Reddit the company doesn’t care about third party app devs leeching off their product. They cost them money. They don’t give them anything in return. That’s why they started charging for the api. 30 days is more than enough to simply increase your existing subscription costs and remove free access. I say this as a developer myself. That’s a half a day job at most, including taking a nap.