You can still learn it by reading books, it’s likely that the person you learnt from didn’t have anyone to teach them like they did for you, but rather they learnt from reading books and articles online.
I still support what you have said, though it’s not everyone that would find someone to teach them face-to-face, but if you can, then it’s a good thing if you go to them to help you out. Just like the time I was into forex trading, there were lots of my friends that were into it then and I didn’t even read a book about it, I just watch them trade and I learnt from it. Then I later switched to binary trading which is a bit similar, and since I already knew forex, there wasn’t much to learn, same with cryptocurrency trading.
it would be better if you learn something in the book, and this applies also in how to learn trade. maybe everyone will have a different view, and there are some of them who need a teacher. this will be difficult because we do not know whether their ability has been certified to provide lessons for people or not.