You’re assuming the opinions of people who didn’t care enough to give their opinion. Unless you can read the minds of millions of people at once, you have no basis upon which to make this claim.
No, it would be completely different. It would be an earned resource instead of a 30-second cooldown, it would be questionable whether or not it was a good idea to use it for a single downed ally, and it would most importantly affect multiple targets instead of just one.
You should have a look at Titanium’s thread Why I Have Yet to Not Despise Mercy's Current State. Specifically, check out the “A Solution” section down at the bottom of his post, which describes in great detail exactly the kind of changes I have been proposing to the Resurrect ult for a very long time. I’m not crazy about the Pacify ability on E and would prefer a mini Valkyrie instead, but it sounds like you haven’t invested much time into actually reading up on the great suggestions for the hero the community has had beyond #RevertMercy.