it isnt in many cases i think.

in those it is it is comparatively difficult to windows,macos and android.

though to compare them in a non technical manner:

imagine windows and macos being the very polished linear game. every step is foreseen by its designers and as long u dont wander off everything is perfect.

linux is the open world mess. quests and things to do everywhere and thousands of people were involved.

linux is much much much easier to use on a higher level. because once u wander off windows and macos are basically dreadful