Tech companies tend to be strongly controlled by the founders/early employees/ and early investors. These are all people who bought in to the vision of the company .. they are by and large true believers. In younger tech companies, like Google or Facebook, this control is truly absolute. There is nothing public shareholders can do.
But even in older companies like Apple or Microsoft, the founders have an almost religious appeal over the stakeholders, particularly employees and the board, but also the shareholders at large.
For example, Tesla and Spacex, though within Icahn's "striking range", might as well be subsidiaries of Musk enterprises. There's no way someone like Icahn would have a chance of besting Musk in a showdown.
