Learning the fundamentals doesn't mean not doing actual programming at the same time. You have to code to have a better understanding on the fundamentals.
My personal experience is that after many years of programming, the fundamentals I learned in school still help me get better. There were many such moments that you were digging into some interesting technical topic and you suddenly realized that some fundamentals had another layer of meaning or application you didn't know or I didn't fully understand before.
Also, understanding different types of programming languages, like OOP, FP, logic programming, declarative programming, etc. help improving one's programming skills, no matter what programming you primarily use at work.
Learning the fundamentals doesn't mean not doing actual programming at the same time. You have to code to have a better understanding on the fundamentals.
My personal experience is that after many years of programming, the fundamentals I learned in school still help me get better. There were many such moments that you were digging into some interesting technical topic and you suddenly realized that some fundamentals had another layer of meaning or application you didn't know or I didn't fully understand before.
Also, understanding different types of programming languages, like OOP, FP, logic programming, declarative programming, etc. help improving one's programming skills, no matter what programming you primarily use at work.