if you look at the last few weeks of commits, you can see they've been systematically ripping out everything bun-specific and moving to node

I think frankly OpenCode is delusional to think that Anthropic is actually "concerned" with them in any way. Anthropic's concerns at this point are on the geopolitical level. I doubt stamping out ToS-violating usage of their subscription services is even on executive radar. OpenAI only allows it because it's a cheap PR win and they take those where they can get them.