These have a long history in tech. My understanding is they were illegal, or at least ignored, in California. I always found it bizarre that someone could make you sign a document preventing you from working where you want, in your chosen field. This is simply a ploy to keep wages down. If people steal intellectual property, then punish them for that crime. Stopping a person from working for a competitor out of fear of a potential crime being committed has always been ridiculous.

FTC intends to ban noncompete clauses that bind 30 million US workers