I don't get all the hate either to be honest.
Just for the record, we made the playoffs last season with Jason Collins as our backup center. Collins plays decent positional defense and sets good screens, which is really the extent of his abilities. He rebounds like a small forward, he's not a shot blocking threat, he misses shots 5 feet from the basket, he has no jump shot, he's foul prone and he is incredibly slow.
The previous season we made it to the ECF and almost knocked off Miami with Ryan Hollins as our backup center. When we signed Hollins the only plus side for him was the fact that he was a relatively agile 7-footer and that was about all he had going for him. He was known as a horrendous defensive player, an utterly useless offensive player and a horrible rebounder. He was also known as a guy with zero Basketball IQ and a pretty so-so attitude. He didn't fill box scores, but he had some solid games for us and made some impact just by bringing strong effort and good energy. Our team didn't die with him on the court.
Fab is raw - we are all well aware of that. The guy has only played competitive basketball for something like 3 or 4 years and is competing against guys who have probably been playing since they were 5 years old...it's going to take him time to catch up instinctively. He's also only 23 years old and quite physically gifted with his length, height, strength and mobility. On offense he has developed a nice little hook shot that he's hitting with some consistency as well as a pretty smooth midrange jumper, decent touch from the free throw line and decent passing ability. Defensively he has already does a good job of using his length to force opposing players into difficult shots, he is already a top-calibre shot-blocker and he's shown he has the end-to-end speed to chase down transiton plays defensively. That's already a bigger skill set then either COllins or Hollins ever had, and he's picked all of this up in his first 3 or so years of playing basketball.
By no means am I saying he'll be a star, but I think he already has a promising skill set, and that his instincts will improve dramatically over time. The Fact that Javale McGee is still playing big minutes and getting paid big money indicates to me that Fab has plenty of chance of becoming a productive NBA player. In fact, if I were the coach I'd slot him in as a backup Center this year for 5-10 minutes a game and just see what he can do. We aren't competing for a title this season, so we really don't have much to lose.