MSS: Rabbi Pruzansky has a lot more experience in dealing with the MO OTD crisis than you will ever have, with his large MO congregation. If he put the number at 50%, that is something he would know of from dealing with it. He wouldn’t publicize a percentage unless it bore out or at least correlates from what he was seeing firsthand in his own large community that he ministers.
And I can advise you from my own experience dealing with otd fellows in the yeshivish and chasidish communities that the percentage there is not even a drop in the bucket compared to what Rabbi Pruzansky is relating. By us we are easily dealing in the low single-digits.