My PMs at Microsoft were all good at tracking tasks/projects and managing blocking issues. At a minimum they saved me a lot of headache having to answer why a task was late when I was blocked by a dependency. They also had quite a few technical PMs, my brother was actually a PM there before I started after getting his Bachelors and Masters from MIT.

AT&T's PMs were a totally different story. Not only did the PM team outnumber our dev and test teams, most of them were tasked with being product owners for insanely small features. Consider having a PM literally responsible for how a light switch works in home automation, that's the level they broke it down to. Some of the PMs lacked skill or experience, but all were expected to do very little of value and were considered to be successful if they were in meetings nonstop to take notes and give them to the next team in line.

PMs can be vital parts of a tech business, but only when they are given real responsibility and expected to create value rather than countless piles of noted and calendar invites.