I don't really agree that he can't evaluate pitching. You're premise that they haven't developed pitching isn't wrong but the reasoning IMO is. The issue is more complex than people make it. They don't look at the reasoning why the front office made the decisions they did. Now I'm speculating here but I'm willing to bet my reasoning is pretty in line with there thinking.
To start with, pitching in general is a giant fucking gamble. You guys remember Mark Appel who went 1-1 out of college? He's no longer in baseball. Jon Gray and Kohl Stewart were also in that 2013 draft as top 4 picks. Kris Bryant was the right pick. And I mean I can go on and on here. So, if you know pitching is a giant gamble, focusing the rebuild on hitting is much safer. I think most people get that part. The part they don't understand is the plan wasn't really to fill the teams pitching needs via the draft. Because they so heavily invested(wisely) in hitting they had a boat load of money to go after FA pitchers. And that's largely what they did. So, knowing that was always the plan they focused on safer pitchers who were quicker to the majors. Basically think of it like this.... if you know you're going to buy your #1 and #2 starters in FA you can focus on safer pitchers who can be 3-5's.
The issue is they went to conservative on their choices. That's not speculation. Members of the front office have said as much. The thing people also need to understand about the draft is it's not just where you pick. It's how you allocate your money because there's a limit to how much you can sign draft picks for. In the case of like 2012-15 they would often focus a lot of their picks on college seniors because those players sign for less than the value of their pick. That enabled them to use the left over money to sign a lot of their hitters. But as the saying goes you get what you pay for. The one case where this wasn't really the same was 2014 with Schwarber. He actually was signed for less than his value. That allowed them to spend money on Dylan Cease, Justin Steele and Carson Sands. Sands was a bust. Steele is an ok prospect still but not earth shattering and obviously Cease blew up big and was a big part of the Q trade.
After 2015, they started to change their philosophy. 2016 was a bit of an issue because they lost their first 2 picks. That draft they pulled Tom Hatch, Tyson Miller, Matt Swarmer, Micheal Rucker, Dakota Mekkes and Duncan Robinson as well as Bailey Clark and Chad Hockin who look interesting as relievers. Now truth be told, the only one of that group that looks like someone who will make the rotation is Tyson Miller at this point. But Hatch yielded them Phelps at the deadline and Swarmer and Robinson both should be good depth at AAA next year. Rucker and Mekkes look like they could be actual future bullpen arms.
In 2017, they took Little and Lange at the top but they also got Cory Abbott, Keegan Thompson, Erich Uelmen, Jeramiah Estrada, Tyler Thomas, Rollie Lacy, and Peyton Remy. Lange was the piece to get Castellinao. Lacy was to get Hamels. Tyler Thomas got Jesse Chavez. Little is still a work in progress but he had 48 k's in 48 IP last year with a 3.56 ERA across A/A+. Abbott dominated AA with a 3.01 ERA and 10.19 k/9. Thompson got hurt early in the year but he's looked really good in the AFL. Uelmen had a 3.05 ERA at A+. Estrada has had several injury set backs and he was a HSer anyways but scouts still like him. Remy had a 2.80 ERA at A.
In 2018, they took Cam Sanders(2.94 ERA in A this year), Riley Thompson(3.06 ERA in A and scouts rave about him now), Kohl Franklin(2.31 ERA at A- as a 19 year old) and Paul Richan who was sent to detroit with Lange. And none of that is to mention any of the success they have had internationally with Brailyn Marquez, Adbert Alzolay, Yovanny Cruz, Richard Gallardo and Oscar De La Cruz.
Point here is, developing pitching is not only risky but it also takes time. A generational hitter can get to the majors at 19 and most good hitters are there by 21. Hendricks debuted at 24. Jacob deGrom didn't debut until he was 26. Those first 4 drafts they were too conservative and that's biting them some now. But the last 4 drafts IMO they've done a very good job of identifying pitching.