Exploit you with industry leading pay and perks?
Unions are designed to balance out monopolistic / low pay / highly geographical companies like large auto manufacturers or airlines. There is so much competitive hiring in tech, it’s one of the easiest careers to switch companies if you don’t like who you work for.
You’re not “free” under a union either, you’re just swapping one boss for another. Except now your new boss wants a cut of your paycheck, for you to be a nameless cog in the system who has to put in time instead of effort and for you to be willing to go without pay for a period of time if they tell you to, while putting up with the same (or worse) bullying and intimidation tactics if you disagree.
Unions are great in some context, but for white collar careers with competitive pay and hiring practices in place, I can’t see it working out well, especially now that you can work remotely at most companies and literally choose any modern, remote-friendly tech company / startup within a few time zones of you.