It could be a nervous grin and not intentened to be hurtful
Watch it if its on DVR. It's a big celebratory smile, like he's about to high five Harrison. If anything, a ref sees that and is likely going to take that as disrespectful. It's the same big smile when a foul gets called on him. My take on it is that it's deliberately disrespectful of the ref's authority, and also oblivious to game situations. After the elbow that frankly cost us any chance of beating Butler, Obekpa's post game bravado was anything but apologetic - something on the order of "I'm glad I took the hit. The guy deserved it."
It seems most of us excuse anything during a win, and turn on everyone once we lose.
But everyone is entitled to opinions as you are to yours.