I love the full-fullscreen mode for things like VSCode and FreeCAD on my 13" MBP. Never have a real issue with alt-tab though I must say I do end up paying attention to it more when I am switching between three windows and not in a cyle.

I have tried to get this in KDE Plasma 6 (with a global menu bar) and you just can't quite get there, so you have to settle for maximised but not full-screen apps, which is annoying.

I understand the difference and the architectural history that is that "full-screen" on X/Wayland is essentially a kiosk/don't-interrupt-my-game mode, whereas on the Mac it is chromeless windows on a virtual desktop that you can't get stuck in if you forget the restore keystroke.

But it frustrates me I can't get that.