In my experience low wings were much easier to land for inexperienced pilots (as the wings get solidly into ground effect - high wing planes are often basically at the top of ground effect).
_maybe_ it makes a difference within the first few hours of training, but once one is able to land consistently the difference is negligible. The minor differences between different planes in general is far more noticeable than just high vs low (and "in general" most small planes land very similarly anyway)
The big reason for high wing bush planes is for ground clearance, and to avoid damage from debris kicked up by the wheels.
As I understand it, biplanes have an adverse lift/drag ratio, making them less economical to run. This is different factor than having a balance between good center of gravity yet also maintaining wing in ground effect. For example, biplanes are still used for certain air show sorties even if they aren’t the main event.
