That's really sad, and it's also sad that he had to make a public admission of this instead of just taking it to the confessional, like everyone else whose sexual conduct has fallen below the standards expected of him or her as a Catholic, according to his or her state in life.
I don't know if he ever did
those things whatever-it-was to/with those priests who complained decades later, although it certainly seems more likely now. I don't know if they say he apologized to them at the time. Obviously to all today, if your spiritual director touches you inappropriately, tries to kiss you and tells you out-of-the-blue he that he loves you, he owes you an apology. And obviously if a priest makes lewd remarks to other priests, or a bishop makes lewd remarks to priests, whom he may think of as friends, but are also his subordinates, he owes them apologies. And maybe, if these things happened, Cardinal O'Brien did apologize and did go to confession. As yet we have no way of knowing.
I mention these allegations because as personally damaging as inchastity is, it seems to me that attempting inchastity with students and subordinates is much worse than just inchastity in general, with self, friends or friendly strangers, or (maybe) prostitutes. Meanwhile, all that Cardinal O'Brien has admitted to, right now, is inchastity.
Of course Catholics would prefer it that priests, bishops and cardinals did not commit any sexual sins whatsoever. We'd prefer it if nobody did. We'd prefer it if we didn't. But, sadly, a lot of us do. And unless we are dragged up on the carpet because these sins happened in the context of work, we confess them to a priest in the confessional, and not to the entire world
As for those saying that the Cardinal is a hypocrite just for having sexual sins on his conscience, they might want to remember what he said back in 2005, when he was defending the presence of gay teachers in Catholic schools: "I don't have a problem with the personal life of a person as long as they are not flaunting their sexuality." He may be a sexual sinner, but I don't think he's a hypocrite.