College basketball recruiting has completely changed with NIL and the transfer portal. Basically every year a coach has to re-recruit his entire roster all over again, to keep those you want to stay from transferring, and to recruit from HS and the portal to fill out your roster. Often times it's a moving situation not knowing who will transfer out, who will test NBA, who will stay, who will come, and these are often intertwined, and decisions delayed until the last moment possible. With NIL, scholarship spot availability is no longer a show stopper if you can find NIL deals to cover that.
All of that means it should be clear by now, to both the coaches and the players, that everything is in play during the off season, constant moving parts, if the school gets another player that shares your position, then it will affect your minutes. If Pitino told the kid they are done recruiting for that position and this happens, probably not a good look, if both sides know going in that this could happen, then that's just how things work now.
We also don't know what conversations happened before JG3 and Symir transferred. Probably told they are moving in a different direction and let them decide to transfer as soon as possible. I have to think despite the nice farewell messaging from them there has to leave a bit of a sour taste.
Look at Quadir Copland, you don't think with the anticipation of JG3 graduating, Mintz heading to the NBA, that he would be in a good position for major minutes next season? But with JJ, Westry, Cuffe coming, and Mintz returning, you don't think that was a big surprise to him? Good thing that Copland is a team player and opted to stay.
This is just how collage basketball is now. The only thing that matters is what was said between Pitino and this kid when he decided to follow him to SJ. Did Pitino promised that he will start or did Pitino say he will always look to build a better team.
I will say that every time a kid transfers out of a program, with the exception of getting way more NIL money elsewhere (like Jesse), the kid probably felt they got screwed (promises not kept, opportunities not given, treated unfairly) to some degree.