Cases where companies actually take someone to court are almost certainly not very common and tend to involve high-level people (or employers with a real grudge).

But having worked for a very small company for a number of years, we wouldn't touch anyone with a remotely relevant non-compete. As far as our business office was concerned, no one was basically worth any risk of litigation and legal bills.

That said, I have known companies that were apparently known for enforcing non-competes and departing employees who wanted to put out their own shingle for competing services would sit "on the beach" for a year before doing so.