Do people use it much in their jobs?

I can't remember ever actually using it other than for puzzle-solving (like the excellent Advent of Code problems). I guess it's pretty common to use leet-code type problems for interviews, which maybe counts, but even there hopefully most employers aren't clueless enough to give people DP problems.

I've done some stuff around generating puzzles/levels/challenges for games that maybe could have used it, but it seemed like problems it might be useful for never came up for me... maybe because I found that you get better, funner puzzles and can control the difficulty better if the generator sort of "thinks like" a human solver/player would.

No doubt there are some edge cases, but how much are people really using DP at a job?

You don't use all them algorithms explicitly. When have you last done a sort?

However if you know them, you have an intuitive understanding of what your libraries do and are less likely to end up on accidentally quadratic.