About the law firms, part of the job of a law firm is to give the corporate employee a "guarantee" that he won't be held accountable for doing something legally stupid. So a new lawyer is at great disadvantage if he don't have the contact he has build trust with. From a freind's law company with 50+ lawyers I know that junior lawyers fresh from uni need at least 4-5 years to build their client base. Then, they can leave and start their own taking part of that client base with them. This limits the number of people who can start their own company and most of them won't risk it in the age of AI, because it will be sales and marketing that will feed them, not their legal wizardry, especially when tasks like "check this agreement" won't be billed at the current insane rates.