It doesn't run GNOME Shell, which is the main memory hog of GNOME.

It uses some GNOME services, namely so it doesn't have to invent it's own. None of these services are memory heavy and all have a purpose (e.g. managing Bluetooth)

weird, I'm running GNOME on my laptop right now and I checked and it's using 275mb of ram. I would not call that particularly bloated.

Phosh is not based on gnome-shell and nobody cares if you want to run openbox on your phone.

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