The new mercy Nerf made her really useless and i let me explain why,
Before anything mercy as a healer have 3 special catgories (main heal/off heal & area of healing/single target healing & passive self protection/offensive self protection) which will be compared with the other healers in these categories:
Main healers: Mercy is a main healer which means she does in average more healing than utility.
The hps (healing per second) of every support is:
Ana: 93.75 hps
Moira:80 hps
Mercy: 50hps
Conclusion: for a main healer Mercy is the weakest healer by quit a lot…
single target healing: Mercy can heal only one target at a time
Ana: Heals from long range to prevent her from getting hit in the battle field
Zenyatta: Heals from long range to prevent her from getting hit in the battle field
Mercy: Can only heal her target in close range making her vulnerable inside the battle field
Conclusion: mercy is the only single target healer that needs to be close to her target to heal it.
passive self protection:
Moira: Can fade out of trouble, invulnerable for 0.8 seconds
Lucio: Can boop targets away from it and escape using his speed and wall ride
Mercy: Can fly to the closest player-dead or alive.
Conclusion: Mercy’s self protection depends only on other team members location while the other passive self protection’s heroes depend only on their cool-downs
All of these features making Mercy the worst support to take in 95% of the situations (With the exception of Bastion and Pharah).
And if you would ask me- I think Mercy is dead…