I don't see how it is a threat. Assuming Godot obsoleted all their code entirely, that would still be a boon -- that's now code they don't have to spend time maintaining anymore, and they can just reuse that and focus on their core competency. (Maybe it's hosting, I don't know enough about this business)
Different languages actually isn't as bad an issue with this type of thing, as the idea with running it in the browser is that it all compiles down to Javascript or WASM.
Different languages actually isn't as bad an issue with this type of thing, as the idea with running it in the browser is that it all compiles down to Javascript or WASM.