I'm on iOS 14.4. "Download iOS updates" (Settings > General > Software Update > Automatic Updates) is deactivated (possible since iOS 13.6). There's still no red badge on the Settings app for iOS 14.4.1, which was released about 2 weeks ago, so it seems like iOS actually stops actively searching for OS updates if automatic downloads are turned off. I find that quite hard to believe. Would be glad if someone could confirm or refute that.