There is a very high barrier to entry (capital) and its only going to increase, so doubtful there will be any more player then the ones we have. Anthropic, OpenAI, xAI and Google seem like they will be the big four. Only reason a late comer like xAI can compete is Elon had the resources to build a massive data centre and hire talent. They will share the spoils between them, maybe one will drop the ball though