They are not wrong. If I were to go back then the situation for me would be quite different. If your intent is to go for a tenure track position then you have to put up with all sorts of stuff but if your goal is to learn and write a thesis with the intent of going back to industry then you'll have a much easier time. The usual teaching and class load is easy to handle and you don't have to worry about grants and all the other stuff especially if you have a bit of savings.

The difference is between maximizing tenure-track job prospects vs learning. Surprisingly those two goals can sometimes be at odds and that is usually what you hear about on HN. People that were trying to maximize for both learning and future job prospects inadvertently running up against academic bureaucracy. If you have a clear goal then you'll have a much easier time.