But he's not. He is a mismatch against most teams with 6'6 sg. I put money on victor being the better player in the pro.
Unless they are posting him up, size isn't that big a deal on the perimeter. Moving your feet is what is most important. Most teams in the NBA don't post their guards very often anymore because it isn't very effective. Even back in the old days team's had a tough time posting up Mugsy Bogues and getting anything too productive out of it.
The size disadvantage would effect a perimeter player's offense more than his defense. But CJ McCollum is an exceptional offensive player. I don't think it will be a problem for him.
Just my opinion though. But at @14 I would take him over any other SG out there.