ppg is an irrelevant stat without context. This has been discussed throughout the thread. Also, what does ACC all-rookie team matter today? That team went 11-21 and the coach was forced to retire midway through the season. We've had a season and half to watch him play. Use this season.
You can use several different metrics for complete comparison of players across the conferences or D1.
For example, here's
Evan Miya's advanced analyticals, BPR. There are 117 players in the ACC who have had played at least 450 possessions. JJ is ranked 57th. 57/117 = 48.7%, so he's been more productive than 51.3% of the players who have played as many possessions has he has. Slightly better than average.
34% is the ACC conference average. If you look at that, that number is made up of a lot of role players chucking threes. If you limit it to the guys playing and shooting, say more than 20 attempts, the average is 34.6% and if you limit to the guys shooting in volume, JJ Has taken 45 threes, so let's use that as our minimum, the average is 34.3%.
So the answer is 34%. As of today, JJ is shooting 27%. Last season he shot 32.4%. JJ is below average shooting the three.