People forget this head to head
15 - 6
or
11 - 6
When they both were winning slams.
Furthermore Nadal is the king of clay, nobody is voting against that. The fact that he basicly wins every tournament on clay enables him to increase his head to heads against various players not just Federer. Look at the head to head against Djokovic 14-5, due to mostly clay wins. HC 3-5 for Djokovic.
It is not that it is not impressive, but just looking at the head to head is pointless.
Djokovic is better on HC
Blake is better on HC,
and others as well.
In fact he is manipulating the stats by winning all the clay tournaments
If you look on head to heads for all different surfaces we get a different picture. Don't use the head to head to discredit players. It does not seem fair to me to only look at Nadal's best surface and judge based on this whether Federer is a better player than Nadal or not.