Ana in general isn't great on KOTH. Even during the height of Ana meta you'd sometimes see Zen ran instead of her on some KOTH points. She also makes a pretty sub-optimal support to run with Pharah because Pharah requires too much attention. Pharah is all about taking some chip damage that you want to heal up off and on so a great Harmony target or Mercy staff target but not so much an Ana who would have to refocus her sights to get heals to her. In general with a Pharah and on KOTH you want a Mercy or a Zen. Often times I run Zen because I find his Trance is better than Rez in most situations where people are forced to team fight in a small area.
I get it is annoying to feel like you're giving in when someone is complaining in text but it is often better to swallow your pride for the sake of winning. Also sometimes it really is the support's fault for DPS constantly dying. Either the supports are positioning themselves poorly or being too obvious a target and sitting in respawn cycle constantly. Zen and Mercy especially can suffer from being out of position and dying immediately.
