This is more a statement on how many bad project managers there are rather than on the role itself being useless. I've worked as an IC with a lot of PM's over the course of my career - I can definitely bring to mind a few PM's that left a huge impression on the project I was working on. I can think of many more that were completely worthless. I think the latter group makes developers think the role itself is useless, which I could not disagree more with. Developers are absolutely terrible at balancing business and customer priorities with technical ones, and the worst part is, many of them believe they aren't bad at that.