That point is when Tesla starts declining in absolute terms. And Tesla grew 35% in 2023. To be a long-term positive, dismissing Musk should produce even higher growth rates- which sounds extremely implausible. Conversely, the probability of Tesla falling into irrelevance in a future without Musk is extremely high.

If they fired Musk, he would wage a never-ending scorched earth campaign against Tesla, and as an executive he definitely has access to a lot of internal information that would allow him to inflict a ton of damage. At this point their only practical choice is to maintain the status quo by submitting to his demands.