As a Zenyatta main (plz don be trigred), I can say he requires a decent amount of skill, Vorp. Perhaps less so with the new patch. Okay, fine, Zeny went from hard as hell to play, to being just about one of the most dangerous heroes, even without a complete grip on him (not that I don't).
And on Symmetra? She is a defense in most ways. If you experienced the beta, she was a full blown support. The ability to give 50 shields made her amazing, but she got nerfed hard, and basically is only a defense at the moment. Her teleporter, however, is basically a better Mercy ult. The main reason she is in the support category (oh yeah and her turrets cause slowing but that's negilible).
It's cool dude, like I said I've played about six hours on him myself. I found that mostly it came down to your position and your accuracy of his left clicks. Since being on top of your orbs is really just a matter of practice.
I never said he doesn't require skill, actually I said he DOES require skill in my post. Just not a ton of it, he doesn't have a lot of mechanics that require direct skill compared to....well....Ana.
I'm not saying Ana is the most skill reliant support because I like to or because it gets my jollies, I'm saying it heavyheartedly as a Lucio main. I would say Zenyatta is the second most skill heavy support, since I thought he was the most skill heavy support before Ana came out.
I actually made a Zenyatta video back before he was ever buffed...
I'm not saying it as a condemnation of the other supports, but as a positive to Ana.