Graph theory and algorithm engineering overlap a great deal. And not only in the directly graph theoretic terms like BFS, Dijkstra, Flow, etc, but also in that you need a good grasp of greedy algorithms, dynamic programming, divide and conquer, and several other general techniques.
You don't need to be a good algorithm engineer to secure a high-paying job though. In fact high-paying jobs regularly turn away strong algorithm engineers because they can't pass leetcode challenges.
The advice is sound -- if you want money focus on the flashy buzzword thing, not the actually useful thing.
Graph theory and algorithm engineering overlap a great deal. And not only in the directly graph theoretic terms like BFS, Dijkstra, Flow, etc, but also in that you need a good grasp of greedy algorithms, dynamic programming, divide and conquer, and several other general techniques.