I don't think we'll have more than 2 players. I think it's like AMD and Intel, the LLM is almost like providing hardware. The software that exposes the LLM capabilities to the user is the layer that will be able to differentiate.
The models are just going to be fighting performance/cost. And people will choose the best performance for their budget.
And that's ignoring how good local models are getting as well.
It's not that they'll have their launch eaten by Cursor, it's just that they can't be as focused on user experience when they're also laser focused on improving the models to stay competitive.