In the most general sense, significant algo/data structure knowledge was necessary to even make it through first round interviews.

Off the top of my head, over the course of interviews with a handful of companies, I had to do several dynamic programming questions, topological sort, a couple of backtracking questions, and a seemingly never-ending number of other tree/graph questions.

Again, I'm not saying knowing this means you _are_ hireable, but to many of these companies, not knowing them made you _not_ hireable, whether correctly or incorrectly.