Let's say that what you're seeing is accurate. Is that really a big problem?
One thing I think we fans underestimate is just how different the college game is from the pros. In college you have an elite guy like Lamb often facing off against an ordinary Joe that's soon going to be a substitute phy ed teacher. And since college coaches aren't pro coaches either, they don't need to (often simply can't) teach the finer points of football to win games. They just scheme the match ups.
(As an aside, I think you really see this today in the offensive line positions.)
What I'm getting at is that every guy is going to have parts of their game they need improvement. But the question is "what part"? Specific to Lamb, is there any reason to think that he can't learn how to make himself open? You can't teach the physical skills that he or Jeudy have but you can teach the nuances of the position. And this isn't just the "you can't teach speed" argument because I think a lot of super fast guys lack change of direction skills so it's more than just that one skill.
When a guy that shouldn't bust actually does bust, I think it causes us to go deeper into analysis paralysis the next time. We think we should have been able to proactively see why the guy didn't make it. But it's not true.
The short list of guys that absolutely should not bust in this fantasy draft are, IMO, Taylor, Jeudy, Lamb, and Burrow. If you want to throw Swift in there, I won't argue. So while none are "perfect" prospects like Saquon Barkley or Calvin Johnson, there's no way to tell ahead of time what small flaws there are in their games could be fatal ones. And while there's not enough evidence to definitively decide among these names, you can definitively decide between them and all the others. You may get it wrong choosing between Lamb and Jeudy but at least it was a comparison you could and should have made. There's really no need to decide between Lamb/Henry and Mims/Reagor however.
So, again IMO, with these top names, if you have the chance to choose between them, just go with the guy you like best and be done with it.