I didn’t really see it coming because I didn’t even realize there were Microsoft accounts until shortly before the migration.

Really? MS had consolidated their online services into one login/authentication system years beforehand. Hotmail, Outlook,com, XBOX Live, etc all use the same accounts. It's why I expected they would do that, they'd done it with everything else they owned.

You have to mod everything to avoid telemetry nowadays. I'd be surprised if my dishwasher wasn't quietly sending data to Samsung at this point.