Violations are determined via a legal complaint and review/investigation. Violations are not termined by company A hiring a person from company B.

Non-competes (non-paid out) only put time between companies (in some states it might be beyond the lifetime of the person under a NC). To put that, and not fully pay out at the current salary, puts a uneven pressure on the individual who was pressured into agreeing to it for (unguarenteed) employment.

Additionally, non-competes survive termination by the company.