As the parent said, Tesla's PE ratio indicates that investors are betting on massive future growth, obviously because of Elon's track record of delivering on his promises of new tech (....eventually). If getting rid of Elon caused Tesla to be priced like other car companies, the price would go down by 90+%.
No sane board member would consider that a serious option.
Board members are also significant shareholders, so they’d be tanking their own position (and would be hard to argue if they sold out shortly before distancing him that they had no insider knowledge of it).
No sane board member would consider that a serious option.