Do you think people change over time or not? I have a double impression. But more than that, I tend to believe that people don't change. Only a small number of people can transform their worldview.
By the way, I was trained in abstract painting. And my conclusion is practice and practice again. No secret combinations and techniques. All that I learned in the course - all the drawing teachers tell me about it. And the value of a teacher or artist is that he chose a narrow group of components, and learned how to present them deliciously. He has practiced so much that he can tell the difference between good and bad. So I now treat the training courses as a search for inspiration and focus on a narrow specialization.