I believe that OpenAI has to a certain extent allowed such usage (see: OpenCode, OpenClaw which have OpenAI OAuth built-in). This just opens it up to other developers!

Sign in with OpenAI will be nice. That being said, I feel like it might be difficult/not open to use for casual devs. Hopefully OAI leaves this up, as they've allowed it for OpenCode. https://x.com/opencode/status/2009805930377167233

This occurred in response to Anthropic cracking down on a similar loophole, which tbh made me take it as more of an opportunistic marketing opportunity rather than a generalizable position.

Not disagreeing with you (and based on your other comments you're probably aware of this info) - just adding context on why this is a pretty interesting gray area and I'm similarly curious whether OpenAI will explicitly allow, disallow, or maintain ambiguity towards it.

I find it hard to believe they'll make it official completely, as that's basically giving away free API credits. If they really wanted the benefits of having free API credits they would just do that directly (but I doubt they'd do that in their current situation).