They are already not as generous as they could be (for example, Google on January 20th boasted about accelerated vesting for the notice period of US employees that would be laid off... But employees in other regions didn't get the same terms)

...and they are going to get worse and worse, with future layoffs

Yep, that's what happens when you have labor laws that dictate the terms. It cuts both ways.

1- the laws dictate minimum terms for the agreements, they don't put ceilings on the maximums

2- the regions in which employees got shafted in that way aren't the regions in which employment laws are stricter

That's not how it works in many jurisdictions: if a company does a round of layoffs and exceeds the terms ... those are the new terms going forward for that company.