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.