I disagree with the beginning of your second paragraph. Even when coding just in Python, a solid understanding of the fundamental data structures and algorithms

I disagree with the beginning of your second paragraph. Even when coding just in Python, a solid understanding of the fundamental data structures and algorithms is very important for writing efficient code. Without it, one can't understand the differences between the containers Python offers and their runtime characteristics, and further can't design efficient algorithms that don't repeat too much work.