That doesn't stop companies from asserting that their non-compete is more broad than it is. Once they do, no other company is going to risk having you work for

That doesn't stop companies from asserting that their non-compete is more broad than it is. Once they do, no other company is going to risk having you work for them while that illegally-broad non-compete is in effect. You can sue but it's so expensive you probably won't and the company knows it.