Except that nobody's arguing that you have to work at Tesla, they're pointing out that Elon Musk is a dick.
Just as people can choose who to work for, people can also choose to share information on which employer is a dick.
Just as people can choose who to work for, people can also choose to share information on which employer is a dick.
In fact, being able to the latter is an important part of making the former an informed choice.