In theory it's exceptionally illegal to curtail unionization efforts.
In practice, the law has been whittled away by decades of conservative judiciary decisions and weak department of labor enforcement. This isn't helped at all by the balance of power.
Companies can afford to scare off some degree of workers, especially at the lower end of the salary range. Big businesses can survive shutting down a store or losing business at locations indefinitely. Big businesses can afford expensive lawyers and to indefinitely stay in litigation over union busting efforts.
For workers, it's a completely different proposition. Is Walmart or Home Depot or Starbucks going to want to hire someone that is actively suing another major corporation for anything at all? It's even worse if it's labor rights related, but just suing them in the first place is going to make it a struggle to find employment at a lot of places. That's even pretending they can find & afford lawyers. Or that they can handle the transition period from job A to job B even if it isn't difficult to find job B.
These businesses hold all the cards and they know it. You see similar thinking, though different details, behind Hollywood's decision to just try and wait out the striking writers and actors. They can survive losing billions of dollars in income a year from now with unmade projects; striking workers will struggle to get by with no salary.
I'd be surprised if USB-C was a limitation on phone technology even by 2040. The bandwidth and power delivery capacity are way beyond what are needed now. Data transfers from phones are going to increasingly move to wireless in that time frame too, I expect.
The limitation on the viability of USB-C with phones won't be the actual technological viability of the standard with respect to phones. Instead, the problem for USB-C for phones will be if another standard comes out and starts being used by other devices that do need higher bandwidth or power delivery capability. Monitors, storage devices, laptops (etc.) will eventually need more than USB-C can provide, even with future updates to its capacity. When those switch over to something new, that will be when phones (and other devices) will need to consider a new standard too.