I don't think Claiborne is as bad as most people believe. His criticism is all based on where he was drafted. With the current CBA, teams need production from draft picks to make the cap work. Based on that concept, he is a bad pick because he has not contributed what he should have based on where he was drafted; however, that does not mean that he can't play or can't improve.
Having said all of that and agreeing that the past few years that Cowboys have done a decent job of drafting, I do wonder if they failed to follow their process on the Claiborne pick. It seems that the Rams called them with the trade offer and they made a quick decision to make the trade up. It seems like they were not trying to trade up and didn't really do their homework on Claiborne. The Cowboys seem to do well with draft picks that they meet with and work out like when Callahan had a private workout with Fred or they spent a lot of time with T. Williams. I'm more supportive of Jerry than most, but I feel like the Rams called him directly and the Cowboys just jumped at the offer because the Rams were not asking for the moon. They had never even met with Claiborne. I think the learning issue and lack of mental and physical toughness might have been determined if they had really studied him in detail.
I feel good about the Lawrence pick, because he is one of those picks that they really studied and that they really wanted.
The Cowboys did the same thing with Emmitt Smith and many others. When a guy they had rated highly falls someone will champion said player and they'll go get him.
Dallas had Mo as it's top defensive guy in the draft and ranked 3rd overall after the QBs.
They drafted Mo based on his ceiling ignoring that he wasn't a good tackler (which was known) and that he was injured(broken wrist).
That is why he dropped. It wasn't some mystery.
They had no reason to suspect he'd be a great tackler nor a physical guy year 1.
Hard to lift much weight or gain strength with a broken wrist.
They realize he is small and needs babying thus the lack of pre-season reps. --which has limited his technique.
In time I suspect Mo will be fine.
I do believe you are correct about perception versus his draft status being the biggest issue.
It's like people who never gave Greg Ellis any credit.
Ellis was a really good player for a very long time, he just wasn't Pro Bowl good and definitely not Randy Moss good.
With Mo you've also got a guy who lost his Dad (they were very close) and who had the fan base turn on him.
So mentally/emotionally he has been struggling as well.
But the talent is there.
He still has Pro Bowl potential.