[iofj]

Would you seriously want a lawyer who has learned only from books ? Such a lawyer would have very little experience in representing clients, and would not have learned from experienced lawyers.

Law has tons of grand overarching principles, that are extremely unclear unless you learn how to think about them. Furthermore, I don't think anyone can learn how to interpret conflicting laws, and likely outcomes under complex circumstances in any way other than practicing it under guidance from an experienced judge.

Furthermore a lawyer should be a good negotiator, should know how to apply client privilege in practice, should know ...

And you might say, become an apprentice somewhere. Yes, but if we do that, we'll go back to lawyers being a protected profession : only family of existing lawyers can learn from good lawyers and become good themselves. That wouldn't be a 100% thing but this would make it impossible for 99% of the population to become a good lawyer.

You also don't want bad lawyers to exist at all, because of the damage they can do to clients. You must absolutely prevent lawyering from having a lemon law problem or the justice system will collapse into total randomness. The situation we have now, with the degrees, is a grand compromise that means anyone (with some small amount of money, and little connections) can become a respected lawyer. I wouldn't mess with it unless you're prepared to see massive unexpected consequences.