I think both can be true - they're losing money on the API and they're still charging too much. Which is really where the music stops for American AI investment. I also use K3 now and its perfectly capable for the development work I'm doing. I don't shed any tears for OpenAI or Anthropic.
API are not subsidized. We know this is true from the existence of independent inference providers (a lot of which are crypto companies that would otherwise just be mining if inference weren't actually profitable).