does shen still do well as support?

Not really. He's not the worst support, I suppose, but I don't think I've seen him win as one yet.

Then again, that could be because they always rush Sunfire...

if it's picked enough to be a role assignment on op.gg, i'd say it's ok

Yeah hes good. If you have the option to, pick into shorter ranged adc's like kai'sa or vayne. He still fares well against other adc's and is useful throughout the game, but early game is far more enjoyable when the enemy is afraid of being taunted.

Shen has a good all in potential in laning phase similar to leona. Shen work best with adc like lucian, kasai, vayne, draven in my opinon.