Wouldn't that mean there's no good business case for Reddit to do this in the first place?

Debatable - supporting a small number of users on the public API may be a legitimate technical debt issue, and a running cost as the API can't change without a lot of documentation, release planning to support all those third party stakeholders etc.

If the API is solely for your own consumption, this can be simpler.

Seems to me just better to entirely stop supporting the public api than to make the costs so ridiculously high. I mean then you're _still_ supporting it, yet you've basically scared almost all customers away. Charging a ridiculously high amount seems maybe like the worst approach of all.

I think you've probably described exactly whats happening - they do want to stop supporting the public API, but only for third party clients. There are other API access use cases they want to support. If the pricing kills third party clients but not the new use cases, that seems like a design choice to me.

They would instead rather charge far more money for data access for things like AI training etc, Twitter have also made similar changes to their own API to prioritize high bills for AI training use cases, not third party clients. That's at least how I see this change. The high pricing for these customers also removes the need to worry about the ad tech situation as is the case in the third party clients - you can just offer them an ad free feed at these prices for the training requirements.

I suspect the internal at Reddit desire to have less third party clients may well predate the AI discussion too, given almost all companies in this position eventually want to wind down those clients as history has shown again and again, for all of the reasons discussed in this thread.

Reddit was the only thing that resembles social media I ever used. Was a long time RiF user, as I absolutely hated the default interface. Even moderated a couple of subreddits back in the day (although I sort of dropped Reddit in the past couple of years, so I may be out of the loop).

My fellow mods and all prominent users I interacted with (the vast majority of them not from tech as it was not a tech focused community) were all well aware of 3rd party clients, and many used them.

This is very anecdotal, but amongst Reddit more "intense" user base, I would be surprised if 3rd party client usage was low.

On Google Play I see 100M+ downloads of the official Reddit app. 5M+ downloads of Reddit is Fun, 1M+ each for Boost, Bacon, Sync, and Relay. Many more in the 100K+ range. Thats maybe 10% at most.

I wonder how many power users, heavy users, or content generating users use unofficial apps. The passive lurkers are great for ad revenue, but the people who comment make the site worth browsing.