Many tech workers already effectively have made the salary compromises required by collective bargaining. That’s what salary bands are. Those who think they’re worth more than that become contractors, while the FTEs mistakenly think they’re getting paid the same as everybody else and sleep well at night imagining they have more job security than the contractors do. Creating actual unions won’t change much. The suckers will still self-select into getting paid less, and will be very happy to do so.