Naturally microsoft would want any AI development done on their platform, under their close supervision. But I suspect they would try to secretly sabotage those efforts. So there is a good chance that the GPT killer will actually come from some college club or hacker collective, with a lot of their work done using github, but the secret sauce being developed on their private systems.

Before there is an open source, or 3rd party gpt killer there will be other GPT's that overtake chat gpt, like Apple's thing, and on a commercial level google is also a competitor. So between the tech giants, nvidia, grok, lamma, stable diffusion, claude, mixtral, Mosaic, etc. there is going to be a very dynamic GPT landscape.