The farce that any coach "develops" or hinders the stock of one and dones is laughable. Some guys excel in their one year in college, and some guys are exposed - which is exactly why the NBA has the one year rule in place, to save them from making a costly mistake like drafting a Harrison, or a Selby, or a Blackshear, or a Poythress in the lottery. Some coaches get a lot more 5 star talent than others, and as such, they have more misses than others - simple math. As a whole, if you look at the RSCI rankings every year, at least half of the top 15 guys could be labeled underachievers in college.
Guys like Towns, Davis, Okafor, J. Parker, Wiggins...those guys are getting drafted regardless of what they do in one year in school. What they do after they get drafted has NOTHING to do with anything their college coach might have taught them. You can't teach size, quickness, talent, work ethic. Those are things you are born with or without. Four years with Coach K isn't going to make a 6'7" PF 7 feet tall.
Cal is no more responsible for Davis being an all NBA talent than Self is for Wiggins, or K for Parker, etc. Same thing applies on the opposite side. Self didn't ruin Selby, Cal didn't hinder the Harrisons, and Roy didn't hurt JMM. Those guys simply got exposed once they got to college.