Theres a weird unnaturally biased towards Sakura in the whole Naruto community. Mainly because she's the main female character of the series, so she's the most focused on when it come to representing the emotional side of Naruto.
Kishi designed here to represent common traits in people (such as a little girls first crush (which is common thing we see these days in the real world, girls can't get over their first love), being made fun of when younger and ext, which was suppose to give her a sense of humanity. But I guess it backfired because people don't relate to her at all, and return these feelings with a dislike for her.
However I love Sakura, unlike most Ninja in the series, she wasn't born with special ability, or had a demon inside of her, or was born into a special clan. She was kunochi with no special abilities, however after only a three year timeskip, she become one of the top female ninja of her generation.
Arguments I don't like hearing.
"Sakura is annoying always going on about Sasuke-kun this, and that"
Well yah that is annoying, but I guess even though Naruto is doing the same thing doesn't make a difference.
"Sakura is so worthless, she never does anything in the manga"
People who say this just turn a blind eye to everything Sakura does. She saved Kankarou, Found a antidote for Sasori's poison, defeated the hariko puppet, the thirds puppet, it took the combined effort of Chiyo to defeat Sasori neither could have won without the other, healed Naruto's wounds, Saved a little girl from the centipede, Healed hundreds at the hospital, saved Hinata, gave up everything to try and get Naruto to come home and to save him from suffering any more pain by killing Sasuke (which was never to happen, he's plot protected), She's one of the main medical specialist in the army, found out neji's zetzu clone and pretty much saved the army.
But with almost every female character, their pretty worthless compared to thier male counterparts. Kishi said he was never good at conveying females or female emotions, maybe that why people can't stand her, because Sakura's emotions, are what a guy thinks a girls emotions would be. But we see evidence of Kishi trying not to be so sexiest, such a Kohnan, and Mei, but I think we'll see Sakura do something amazing near the end of the manga, to show her haters "shannnero" or whatever she say in japanese which english loosely translated to "hell yah!"