They didn't even need to do that. They could simply have changed the terms so that user-facing clients like apollo either need to show reddit ads, allowing no ads for users of reddit premium. They approve api users anyways, supposedly, so mod tools and the like could be exempt, and they could introduce higher cost efficient bulk export of comments for large scale generative AI machine learning use cases.
Instead of being the shit-show it is now, it could have been a good money maker.