delta v isn’t really a issue if you have orbital refueling and frequent+cheap flights figured out (as long as a full tank can complete a trans Martian injection and orbital capture at mars) , so I’d say they’re both similarly difficult:
on Mars you have to deal with the atmosphere, higher gravity, etc
on the moon you have to deal with the dusty surface, so you have issues with landing gear and landing engines kicking up dust
delta v isn’t really a issue if you have orbital refueling and frequent+cheap flights figured out (as long as a full tank can complete a trans Martian injection and orbital capture at mars) , so I’d say they’re both similarly difficult:
on Mars you have to deal with the atmosphere, higher gravity, etc
on the moon you have to deal with the dusty surface, so you have issues with landing gear and landing engines kicking up dust