The WP 48mm forks do have a lot of friction. One big problem are the seals. SKF did make special new seals to help solve this problem. They are standard in the recent KTM models. There is a You tube film about these seals. What they show is true.
A lot of people complain about a firm feeling with the KTM's. They don't filter away the hard firm small bumps but still dive down when braking. IMO the discomfort comes from the friction.
The 48mm WP that I used for my ST did the same thing. I think it was the worst fork I ever felt.
There was a lot of movement between the inner and outer tubes. Even with new bushing.
This pushes against the seals. So more friction and the seals will wear out faster.
I used feeler gauge to shim out the bushings. Its a terrible job and will take a lot of time.
But for my fork it helped a lot.
The pics just show "where" to put it. Make sure its al the way round the bushing.