Not necessarily.
Karl was part of that "platoon" and he's likely to be the #1 NBA draft pick. Willie and Trey will both be lotto picks at worst. Devin was part of the "second platoon" and he's a first round lock bordering on lotto. Dakari is late first round in most of the mock drafts I've seen. Davis and MKG showed that sacrificing and not "getting theirs" the way they could've done at other programs doesn't hurt you in terms of national recognition, historical significance, or draft status.
On the flip side, though, the Harrison's stock didn't improve much, if any, but to me Andrew was a MUCH better player this past season than he was as a freshman. He played with so much more confidence, poise, and leadership. He doesn't have blazing speed like the prototypical NBA point guard, but to me I think he should be a late first round pick and at worst a lock to be a second round pick. Aaron is the only one that probably hurt himself with the way he shot the ball from 3 in the regular season, IMO.
The only way that I see "the platoon" hurting UK is if you're a recruit whose main concern is "getting yours" and being "the man" and not playing unselfish team ball with other great players. As for coaches that will use that against UK in recruiting, the smart recruits are going to see right through that and take a measured evaluation of the situation and how they would fit in instead of simply believing the sweet nothings being whispered in their ears as the gospel.