My job forced my coworker to remove his pride flag stating no flags were allowed. Even though other coworkers have football team flags at their desk.

Can my coworker do anything? The state of Michigan btw. Edit: The decision was made by management after other coworks said they wanted a “straight flag” hung up. One coworker went as far as saying “I’m bringing a nazi flag in then.” He argued that he only wanted to put it up for “ pride month and then he’d take it down, but no dice. (His brother is gay and he’s really supportive) As a spectator of the drama I’ve never seen so many people get so upset over something so small.