a citizenship cant just be revoked due to not liking someone..
citizenship is more of a permanent thing compared to work/resident/student visa's, which can be revoked easily
there are only a few conditions that would allow revoking a citizenship, and the most used one is where the application and process of gaining citizenship initially is found to have had fraud involved in the process (sham marriages for instance)
A press agent can't just be revoked due to not liking someone - but it was. A president can't just call in the national guard for nothing - but he does. Trump break rules
the national guard can be called in.. and was, using legal methods.. no rules were broken
press can be uninvited to attend white house press conferences.. no rules were broken
ending someones citizenship is harder than a phonecall.
that said..
.. if trump goes too far against supporting elon for things like the space missions, elon can simply take things abroad and voluntarily seek new citizenship somewhere else, im sure many countries would welcome him