Telemetry is a problem, yes. Should be at least opt-in.
I believe that forced upgrades are a necessity if you have the end-user market penetration of Windows. It's a different thing for servers, and one could argue about the implementation details.
I don't see ads on Windows (and I'm on the 11 beta channel).
Yeah, that start menu area (not sure what the real name is) has panels (I bet they have a real name too) for games and junk. Not to mention how the OS is really pushing people to only use the MSFT Chromium (aka Edge) browser now, similar to how it used to push IE. I'd call that an ad as well, though not exactly what you might think of an ad.
In my experience, ads appeared in the start menu as well as ad notifications on occasion. I removed the ads from the start menu but after an update some of them seemed to return. Similar experience with the ads in the notifications tab. Although a minor experience to re-disable the ads, it was enough to get me to switch. I paid good money for windows, only to get MORE ads than the free alternative
By default, yes. I always quickly follow the instructions online to disable all of that on a new install so I've never encountered them. For me it's no more hassle than the things I need to do on a fresh Linux install.
I haven't seen it push for Edge, in fact I don't think I've opened Edge since install day.
Performance and telemetry if you don't need anything Windows-centric like games are very good reasons. Upgrades though? Even if they are not explicitly forced I'd bet way more people (as a %) are fine using XP or 7 today than whatever version of Ubuntu or other popular distros came those years.
Less bloat. No random upgrades at inopportune times. More consistency WRT the file system, installing software, etc... Not being bombarding by start menu ads or Cortana randomly popping up.
