"many of the straights left long ago". Probably to get married. And once married, JP2 ensured that they were locked out of not just priestly ministry, but also any of the ministries open to the so-called "Laity". Talk about "Father What-a -waste"!
And here's the paradox: if a gay priest wanted to strike up a sexual relationship with another gay person (quite possibly another cleric), it would be possible to do so discreetly so as to stay under the radar. Maybe their bishop (possibly also gay) might be willing to turn a blind eye as long as it only involved consenting adults.
If a heterosexual priest, on the other hand, started a relationship with a woman (very likely a parishioner), it would be almost impossible to hide it. The inevitable "laicisation" would follow. If priests were allowed to marry this nonsense (and waste of talent) would cease overnight.