First Amendment applies to all whether you like it or not.
Little do liberals know the fact that freedom of speech is a double-edged sword. Anything a liberal says, another person can completely contradict. It doesn't matter if the speech offends you on a general level, it doesn't matter if it's against your ideas, it is speech and it is protected regardless of who says it.
This vandal doesn't understand that fact, and they decided to destroy and suppress someone's rights because they deemed it hateful. It is ironic that liberals, who proclaim themselves as favoring civil rights, would so willingly suppress them if it does not fit with their agenda.