Should your waiter, your dentist, your auto mechanic, your daycare worker, your landscaper, etc. have a say in your decisions? They're your employees, albeit temporarily, so why not?

The shareholders are the owners of the company, not employees. The right to set the direction of the company belongs to its owners. The profits belong its owners, just as your paycheck and what to do with it belongs solely to you.

(As an aside on shareholders and compensation, considering how many FAANG people have huge chunks of their compensation in stock, people are well aware unionizing at a FAANG is basically people attempting to pick their own pockets since increasing employee compensation (themselves) is taken from shareholders (themselves).)