The supply of lawyers is restricted through onerous education and licensing requirements. You could argue that the fall in wages means they are no longer as effective in controlling supply. But if you think the supply "isn't restricted at all" I encourage you to start offering legal advice for money and let me know how that goes for you.
I don't see anything particularly onerous about education and licensing requirements for lawyers. A sufficiently motivated student can complete law school and pass the Bar exam in a few years. So in practice there's no significant restriction on supply.
https://www.ama-assn.org/press-center/press-releases/ama-con...
Again, if you think there are no restrictions, hang out your shingle and start giving legal advice. If you're right, you should be fine.
The supply of lawyers isn't restricted at all, as shown by stagnant or falling median wages. Almost anyone who wants to become a lawyer can enroll in one of the "third tier toilet" private law schools, and states don't impose any limits on the number of law school graduates allowed to take the Bar exam.