A tech union seems inevitable at this point. It seems like there has been some false starts, but there is a "market need" that is being unmet. Silicon Valley has shown it's very good at meeting unfulfilled market needs.
While true, how do you do that and still maintain the flexibility of moving from lets say Javascript to Golang or Swift development? A Union would stifle or add friction for people wanting to quit your current job work with different technologies they want to work on professionally.
From what I’ve seen the unions forming in tech right now are way more fluid than the corporations they’re working inside. These are very decentralized federations of employees. It’s not some old Italian family who has been controlling the FORTRAN labor market in San Jose for 30 years.