Governments seldom if ever "make money" by licensing professions. The costs associated with administering a licensure program normally eat up all of the income, usually considerably more.
In my somewhat limited experience, many professional licensure exams primarily ensure that the person being licensed understands the government regulations, not that they know how to do a better job at their profession.
Licensure expands government power, that's its only real rationale. I've never seen any evidence that states with licensure of the more obscure professions actually have fewer problems with that profession than those who don't have licensure.
How is “legal advice” any different from any other speech?
I’ll exercise my freedom of speech right now to give legal advice to all of you to obey the laws that makes murder and rape and robbery illegal.
How is it different is I accept money (or not) for exercising my freedom of speech?