Good question. I'm thinking of a couple of Boston College grads I know who attended St. John's seminary in Boston back in the early 80s. Both left - said the seminary was like a gay bar and they were in the hetero minority. But then when I think about it, if they really had a vocation, maybe they would have persevered or switched seminaries. Look at Fr. Trigilio and Fr. Brighenti - endured a lot in their seminary back in the 70s/80s and held on until ordination.
You guys sort it out! Too many ifs, ands or buts for my limited abilities!
What I thought was sad in my area was when a guy here discerned a calling in his 30s. He was transformed by the Tridentine Mass at our Indult parish, quit his lucrative job and went into FSSP seminary in Nebraska. He came back to celebrate his first Mass at the indult parish and then went back to Nebraska because - no room at the Inn here! One indult parish (which is also an NO parish) and there is already a priest for that congregation, so they didn't need the new FSSP priest. So he left an archdiocese that has a self defined priest shortage. Makes no sense. If, as we hear all the time, the laity are demanding the Eucharist (which crosses all linguistic barriers) and there are not enough priests to distribute the Eucharist, you'd think the laity would be grateful to God to have a priest say the Mass in any language. And I suspect they would! But the chattering ordained class is deciding for the laity that the laity will only accept priests who say the NO Mass.