Funny thing about that. If you want to do it you are allowed.
You only get in trouble if you lie about it.
Quit your W2, form LLC, go back to employer. “Hey boss, I started a new company, me and my team will do just what I did before but now we can scale up and down as needed.”
My business does this. We’ve got ten people and a fantastic amount of work. I was worried that the downturn would hurt us but we have more inbound work now than we did a month ago and we’re adding two new people next week.