But there's a categorical difference between that situation and when an employee or dozens of employees who may be a break even or negative impact on profits have knowledge of a trade secret researched by a team of their predecessors that makes the company $100M.
I'm all about fair compensation and worker's rights, but a business shouldn't have to pay all those people $100M salaries.
However, this might be confusing different issues. My comment was specific to using NDAs/non-competes to protect trade secrets. This is different from merely using them to prevent poaching by competitors. In cases were there isn't inevitable disclosure, I think it's much less likely that a non-compete would be enforced in court.
In fact, this already exists. https://en.wikipedia.org/wiki/Garden_leave
It really should be required of all noncompetes.