That’s why they’re mostly autoworkers or longshoremen and whatnot an not professionals, outside a few niches motivated by ideology.
It sucks both for you and the company if they have to replace you.
In contrast, if you work building SaaS apps on top of k8s, you can both transfer your skills easily, and the company can replace you easier.
It could go both ways, but in practice it usually turns out that if your skills are transferable you make more money.
This thing also popped up in the gaming industry, with Unreal becoming popular, and people using it making much more and jumping between projects, because their skills are transferable.
(Mind you, that very individualism is why they're not already unionized)
This turns out to be a lot harder in practice than in theory.
Gamers are very passionate about their games and the companies behind them. They are also very anti-AI, pro consumer rights, and pro unions. At least the vocal majority of gamers, such as on /r/games, which is where a good portion of gaming journalists get their takes.
It would be the end of id Software from a PR standpoint if they fired union developers responsible for their beloved titles, specifically the recent DOOM titles. The bad PR would also extend to ZeniMax, Bethesda, and Microsoft.
That said, gamers are also the worst at voting with their wallet. Despite all the bad union PR Rockstar North is receiving, pretty much everyone in support of the fired employees will probably still end up buying GTA6 because of FOMO and hype.
Automotive plants have large factories, but when the primary assets are intangible intellectual property, I don’t understand how much power a union really has.