Agree that Reddish's shooting numbers aren't ideal, but it's very easy to read too much into small sample sizes with these super-young guys. I believe the NBA analytics folks have concluded you need 700 3-pt attempts to establish a legit shooting trendline; we won't get that yet with any of these collegians.
You'll also find plenty of scouting misses where a guy shot well from deep, very briefly, at the college level, but other factors (bad shooting form, FT%) indicated that wasn't real. The Lakers in particular are getting burned that way right now with Brandon Ingram (41% from 3 at Duke, but only
68.2% from the line) and Lonzo Ball (41.2% with the funkiest shooting stroke,
67.3 FT%).
In some ways, Reddish's numbers are pretty comparable to guys who figured it out later in their college/NBA careers:
Cam Reddish: 68/200 from deep (34.0%), 77.5 FT%
Otto Porter (two years at Georgetown): 55/155 (35.5%), 75.1 FT%
Buddy Hield (first two years at OU): 109/313 (34.8%), 77.5 FT%
But you're right that it's not at all guaranteed he'll get there. Also, it seems likely he'll have other offensive limitations, ones similar to Porter & Hield (limited playmaker with the ball in his hands, more of a catch & shoot guy) — I definitely wouldn't bank him on him becoming the next Devin Booker.