One thing the Hollywood people have in common with each other, but not with us, is that they move from one employer to the next frequently as a matter of course. Those employers explicitly do NOT want to carry them on their books when they don't have specific jobs for them to perform.
Unionization makes a lot more sense in those cases. If I need a ship unloaded, I call up some dockworkers. If I need some heavy boxes moved, I call up some Teamsters. If I need someone to look good on a screen, I call up Tom Cruise or Jennifer Lawrence. If I need someone to feed the actors, I call the craft union. Etc. Like the old joke about hookers, I don't pay these people to come to work, I pay them to go away.
None of that is comparable to what I do, or (probably) to what you do. Your employer can only become less competitive if you join a separate outside organization that acts as a middleman for your labor. That's not the case in other industries.
That's certainly not the case with all unions like that, e.g. sport players' unions, where a player works for a team for a couple of years, then may go to another team, or (an area where I'm familiar) AGMA, the American Guild of Musical Artists, where many union members are employed by the same dance or opera company for years, sometimes their entire career.
Unionization makes a lot more sense in those cases. If I need a ship unloaded, I call up some dockworkers. If I need some heavy boxes moved, I call up some Teamsters. If I need someone to look good on a screen, I call up Tom Cruise or Jennifer Lawrence. If I need someone to feed the actors, I call the craft union. Etc. Like the old joke about hookers, I don't pay these people to come to work, I pay them to go away.
None of that is comparable to what I do, or (probably) to what you do. Your employer can only become less competitive if you join a separate outside organization that acts as a middleman for your labor. That's not the case in other industries.