The fact that that represents something the folks at xAI think would be entertaining can certainly be a basis for thinking twice about trusting their judgement in other matters, though, right?
The great thing about xAI is that it is just a company and there are other AI companies that have AIs that match your values, even though between Grok, ChatGPT, and Claude there are minimal actual differences.
An AI will be anything that the prompt says it is. Because a prompt exists doesn't condemn the company.
Within the boundaries of pre-training, yes. It is definitely possible, in training and in fine-tuning, to make a LLM resistant to engaging in the role-playing requested in the prompt.