[Jenda_]

I think Ubuntu has some kind of notifier in "tray". For me, I am subscribed to debian-security mailing list and update when something that is running on systems that I manage seems to be affected.

> versus the more automated update systems MacOS or Windows

I'm not sure -- it is better with Microsoft Store, but other apps solve updates on their own, with various success. I have little experience with Windows and no with mac OS, so I cannot comment.