Or just reinstalls it in the next update.

I did that and it was a mess, with warnings about being unable to backup that I couldn't get rid of. I had to reinstall to try to turn off syncing, then remove again. But it's so integrated that my desktop is still under a OneDrive subfolder and it's still referenced in various places.

Is there a guide to completely removing this from Windows 11 cleanly?

Yeah, it's also not "just" if it's one of what feels like hundreds of steps now to make the OS somewhat usable.

It's not an Apple fanboy but imo it's a lot more transparent on their side. There's a switch for each and every service to use iCloud or not in the settings. Services don't just re-enable their usage of iCloud after some random update and most importantly, they don't just re-install apps you previously deleted. Or bloatware.

The bottom has dropped out of the OEM software licence market. Microsoft have to find a different way of making money. Their loss-leading hardware sales have not borne fruit so they are getting desperate.

All they have left is services, which means that the only way the can actually make money is selling out their customers private information.

Except it won't be their most important data. Either their very first files from their desktop (up to 5 GB), or random 5 GB files (no idea which). Once it's filled quickly, it will start nagging about buying more storage.

It is not even close to a good enough reason. First of all, I don't really give a shit about what other people do or don't do on their computers. It is not my responsibility. Second, sneaking in their cloud solution isn't the right move ever.

Let the user decide if they want it, enable it by default I don't care, but don't sneak it in like it's a fuckin trojan lol

I think that it's quite bad if Microsoft puts peoples family photos on their servers without the user realizing it. That's not a niche privacy nerd sentiment, I think that a lot of people would find that creepy. Having the option easily available can be really good for a lot of non-techy people but it should be very clear what stays on your computer and what doesn't, and how to keep something private if you want to, which I'm not sure that it is if Microsoft quietly backs up Documents, Pictures etc.

Actually, my father in law just lost 3 months of work yesterday because he synced his documents folder that had an old copy of his book on OneDrive. None of the cached files had his new stuff. Maybe if OneDrive was made well, it would prevent data loss.