I too really don't think Jaylen would talk **** to a player like that, let alone a top three player in the league.. Believe me that day will come, but not today.
I kept a close eye on Curry this game, he was having an off night having missed 7 three pointers at that stage.
So couple all of..
1) Faking out JB (quite brilliantly we must admit).
2) Making the shot (by means of a "swish").
3) As the 3rd quarter buzzer sounded.
4) Putting his team up by a point.
..brought an opportunity for Steph to exhale his frustrations that have accumulated throughout the game (as listed above), all while using Jaylen as nothing more than a prop in the process.