Ron Carlivati didn't give a shit about Patrick any more than he gave a shit about most men on his shows. If you watch his work over the years, unless he created or brought in that character most males are expendable chess pieces in his stories. Most of the more conventional leads are the goat/dupe or a piece of meat or gender-swapped as the clueless ingenue, or all of the above, usually to bigger villains or vixens, etc. Dante, Patrick, Nathan, Spinelli, Jake/Jason II, Michael, Morgan, etc. That is why Patrick had an offscreen pill addiction story before being turned into a Prince Charming archetype overnight for two new characters (Sabrina and Britt) to compete over. Patrick was never the priority. RC's larger plot machinations with Faison, Robin, etc. always were. For that any character can be misused and marginalized, and that included both Robin and Patrick, albeit in different ways.
I was never some massive fan of Patrick as a solo character, ever, and I see no point in him returning to the show on contract. But the fact is GH didn't give a shit about his character beyond plot function once Robin was gone. They might have paired him with new women, but that was simply a function of a larger plot arc in which logic and plausible motivation regularly went out the window for multiple characters. JT knew all this, which is why he quit. Nothing that was done to him or to Robin was to try to make Patrick happen as some shining solo lead; that's missing the forest for the trees. It was done in part to shine up new favorites like Sabrina (who was always going to lose Patrick but not without RC making sure to try to make people pity her first), but more importantly to further a larger umbrella plot axis with supervillains and the Scorpios - because before Ron Carlivati ever came to GH, he'd already begun prioritizing plot over characters.