Beginners will never really be in a position where they'll be using vanilla gnome, so that argument is kinda moot. And even if they did, those features are literally one extension away...
will quickly miss features like a minimize button and certainly tray icons.
Tray icons don't exist in gnome's ecosystem, it only becomes problematic once you get third party applications.
The real problems are the minimize/maximize, desktop icons, and panel on top when coming from windows. Although these days with the ever increasing phone use people might just be more at ease with gnome's workflow anyways.