Their amazing petition can be found here for more points: 

https://www.change.org/p/rewrite-the-last-of-us-2-story?signed=true

Here's a point that was taken from their petition which i posted a link above. "The number one reason for so negative reaction from fans was HOW Druckmann sadistically executed Joel!
 By spitting on Joel's bloody, battered corpse Neil Druckmann spat in the souls of thousands of fans, thereby disrespecting us. And, believe us, it doesn’t matter whether main character was killed by a gay or transsexual, an atheist or Christian, an Asian or African American. The most terrible thing is the way of killing.The focus was on humiliation and disrespect for the protagonist, but it seems Druckmann just wanted to settle the score with this character. But Joel represents a loving parent who is not willing to lose a child for the second time. We love Joel for who Joel is as character.
Writer is trying to make us empathize with the new character Abby who is guided only by hatred and desire to take revenge and make us believe she is the victim of circumstance.

All his attempts to demonize Joel make no sense: this character was never full of hatred and senseless thirst for murder. Unlike Abby, who killed him in brutal way only because of her own hatred and was not able to forgive him even after Joel saved her life." again go check out their petition for more points (way better points than mine)