According to the CEO, Reddit is losing money. It won't survive long-term if that doesn't change. If people care about reddit and its community, it seems like that's what they should be thinking about.
If an alternate client uses the API, but doesn't return any advertising (or other) revenue, that is a good reason for reddit (as a company) to change that relationship.
To be clear, I'm not making a comment about how they are going about it. But destroying reddit's business is no help to anyone.
Lots of people on reddit (and on here) brag about using ad-blockers. They also complain about paying for services. I mean: something's go to give. VC's won't continue to fund these free services forever.
I'd rather live in a world where you view advertisements or pay a fee to use services. But I seem to be outside the norm on these things.