For context, JHS has a better pull-up 3P percentage (37% on 54 3PA) than premium shooters like Brandon Miller (33% on 76 3PA), Sensabaugh (26% on 31 3PA), Whitehead (36% on 22 3PA), Jett Howard (30% on 63 3PA), Jordan Hawkins (31% on 58 3PA), and Keyonte George (35% on 99 3PA).
Basically, the only lottery-caliber shooter in this draft with better pull-up 3P shooting is Gradey Dick, who shot a scorching 53.5% but only on 43 pull-up 3PA (Saint Cy Edit: I believe most of these from Dick are 1 dribble pull ups).
It doesn't end there. From off-dribble/pull-up midrangers, JHS (42% on 142 2PA) is in a tier with Brice Sensabaugh (53% (!!) on 97 2PA) and maybe Cason Wallace (45% on 58 2PA) and I guess Scoot Henderson (38% on 151 2PA).