Companies can handle that without using non-compete clauses.
As an example, companies I have worked for consider employee and customer lists to be proprietary information. Engineering and management staff sign NDAs that explicitly cover employee and customer contact information. I have known senior management to call managers who left when the senior manager suspected the separated manager of soliciting employees who were still at the first company (to come work for at a separated manager's new place) and "read them the riot act". Current employees were free to initiate negotiations, and some did, which annoyed the senior management but was not considered actionable.