People have no idea what to do with her and since she's new folks are just going to instalock and do horrible.

She should never be the only support on your team, you still need a Mercy or Lucio to fully heal your team. However her using her primary on a teammate before they jump in can prevent another healer from having to following them in and getting killed. Her bomb is great when used on your own team. Her sleep round can be a game changer if he shits the right person and your team focus everyone else down while they're still asleep.

She should be played at a distance, and then she should be on the point while one or two members of your team push out to keep them away from the point. The key is she can still heal from so far of a distance. I love using her when we have a Winston on the team because I have him jump in and disrupt their back line while I heal him and damage the other team at the same time.

Her ult is what hurts pug games at a low MMR. I find myself playing with more quality players so that Genji knows not to do his ult until I ult him first. Put it on a reaper and he should go all in and can take out an entire team. Hell, I've put it on a Rinehardt and had him go ape shit on a team before and they couldn't do anything to him. Just hope your team isn't stupid and stands back after she ults them.