I know this should be obvious, but...

Just because you're a non-offensive support doesn't mean you literally have to hang back at the turret. I just got out of a game where the Soraka wanted nothing to do with supporting and just hung back under the turret. I come back to the tower and type at them to come help, as I'm in the middle of doing so they come towards me and heal me like it means something, I go back and try to farm again and they just go right back under tower.

1. You don't trigger Nomad's Medallion if you're not by the minions. On a side note, you also don't get experience if you're not by the minions when they're killed.
2. As a Soraka, you at least have an AoE silence that you could cast once or twice at the very least to give me an opening to kite. Can't cast it from way back there, of course, but it's the thought that counts...right?
3. Your Ult has a long cooldown and doesn't come until level 6.
4. Even as a non-offensive support, you're there to play League of Legends. What's worse is that the rest of the team actually agreed Soraka should be hanging back at tower, and when the Xin Zhao came to steal all of my farm (dealt with it for a couple waves until I realized it was intentional) I decided to roam and help out. I then get harassed by my team because I abandoned the lane, and when Soraka started feeding against the Xayah I was blamed for feeding my support to them. When I complain to the team that it was the Soraka that fed them, the Soraka spams at me "stop crying" and "report the adc". At the end, when I finally started getting tilted, I called them a bunch of bandwagoning SJWs. Of course I know that was wrong (about them being SJWs), and I only said it once, but of course when they warp it into a heinous act in the All-Chat the enemy team joins the bandwagon.

It's games like that, that make me realize why I stopped attempting getting into Ranked games. I've been playing ADC for a few years now, even managed to get Tristana up to Mastery Level 7. I've gotten my share of Tear-spammers, Swallowers (Tahm Kench) and Troll-abusers (Trundle), Kalista Ult-spammers. I've gotten Zileans that save their passive for the Jungler, and plenty of Mid Laners feed under tower from the point the gate disappears. Supports completely abandoning you, then the team harassing you when you give that support the same treatment? Haven't seen that before now.