Depends.

I've known people who play both. Some say guitar is easier, some say piano.

I suppose it depends on the way your brain is 'wired' or your aptitudes.

With piano, it's horizontal. Bass on the left with one hand, treble on the right with the other. So one hand comps the other plays melody.

The guitar is vertical, bass on top, treble on the bottom. So both hand are playing comp and melody.

So it's whether you can do different things with each hand, or multitask with both hands doing the same thing.

Notes ♫

Bob "Notes" Norton smile Norton Music
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