I did not understand it at forst but I saw a really good explanation on why it was taken out.
Because people abused the range and fast charge.
Let's say you are attacking on Hollywood. Your team communicates well, and makes one if the most flawless pushes every. Zarya Gravitons, Sombra hacks the tank, McCree High Noons, and eliminates 5/6 of all the team. You press select to see who is still left...It's Mercy...And just as you feared, she resurrects the whole team. And just like that your team's push is destroyed. More than likely unless you have 3 other good ults up your bum. Most of the time you won't. Honestly, I think rez should of been fixed, not deleted. Shorten the range and extend charge time. Make the Mercy's work for it.
People are going to complain about this anyway, but they apparantly haven't experienced this, and thankfully never will!~