NCAs are really only valid when you have very specialized knowledge of say a chemical manufacturing process and even then other laws govern stealing proprietary information. They have been greatly abused. Nuke them.
Yep. That's literally the example I was going to mention. There are certain levels in the tech ladder at my company where, rumor has it, you sign fairly comprehensive NCAs**. You know way,
way too much about the secret sauce. There's no way for some people to work for competitors without necessarily divulging information that may be key to the 11 herbs and spices that go into some of our products, for example. Like, even the OEMs for the equipment in some cases are considered TS and protected.
I actually don't have an issue with NCAs at face. However, I do agree that there should be rules and limits that govern them to a fairly narrow set of circumstances. I also thought that NCAs were generally unenforceable if you could show that they essentially prevented you from being employed. Not without compensation.
ACME shouldn't be able to ban someone from working at "ACME Competitor A" who makes anvils if that's one of 50,000 products. ACME should be able to limit your ability to work on anything related to anvils at "ACA" though. At least for a certain time after you leave ACME. Or as Kepler was alluding to, the abusive way they've been used to absolutely screw people.
tl;dr: What fade said.
**That said, if the rumors are true, you're also given a pretty handsome compensation package as part of this. Stipends, allowances, etc.