An online friend can't be there physically in the same way, and so I think it is true that a physical pal has better upward potential. That said there are definitely IRL friends who aren't as nice, kind and fun as online friends and vice versa.
I meant if in both cases the friend is perfect - the one who can be physically present is preferred. As in let's rate a friend on a scale of 1-10 insofar as they can help you in your daily life.
The higher value 10 will not be possible for the online friend as there are certain things they simply cannot do because of distance.