There's no paradox.

The law is you can't descriminate against a protected class. Lots of things are protected classes, like race and religion. Old age is, but young age isn't. Clothing choices in general aren't, but if it's a religous choice, it likely is protected.

Etc.

It's kind of weird that you can fire young people because they're young, but not old people because they're old. But it's not a paradox, it's just how the system is codified.

Yes, from a legal perspective this will always be true: in-group vs out-group. Age discrimination is a special category because everyone will be in the out-group (when young) the age into the in-group. In this case, it is probably legal to fire someone for being too young. It sounds weird, but that is not a protected class of employees.

You would need some class action lawsuit I’d think? Need a good number of laid off people to join it and you need solid statistics that would convince a jury more than the corporate lawyers would with whatever HR covered their assess on paper have.

Is it not fine to just cut for pay rate? That should be easy

People are feeling more alone than ever. But whatever you do, don't do anything communal!

In Sweden,the Employment Protection Act, (LAS ) mandates 'last in - first out', meaning if there are layoffs due to over-capacity, people with seniority (years of employment) take priority for available positions. This is kind of partioned by profession-group, so yes you can fire nurses but keep doctors, or other way around. (Its been a while since I looked into it, but thats the rough gist of it)

China is hiring engineering talent. US is firing. Nobody forces anybody to do anything. Just pointing out the current state of affairs in the long life cycle of empire. As Ray Dalio says US is very late stage declining „financial capitalism”. While China is early stage aspiring „production capitalism”. It is not like late stage declining USSR needed as many engineers as it did when it wasnt collapsing. USA is a collapsing empire. China is growing.