What do pull-ups do for Wing Chun? Not much except maybe give you a good jut sau? Regardless, I also used to do a ton of pull-ups and chin ups.
But I didn't do them to help my WC. I did them for the far more important reason of
showing off!
....Up through my mid-fifties I could do a crap-load of chin-ups and pull ups, even hanging by my fingertips ...and easily beat nearly all my younger students in a challenge. Now I'm much heavier and recovering from a rotator cuff injury (it's been taking over a year) so I can't do them any more.