One of the things they're striking against is arbitrary return to office mandates. Why did you leave off two words that change the nature of what they're fighting for?
Other folks have already pointed out the "rights" unions have fought for that we take for granted today. On top of that, being in a union is about solidarity with your fellow workers. You can support your coworkers' who need or just want to work from home. This should be easy, since it would affect you in approximately zero ways. They'll have your back for fighting for Just Cause protections.