This is such a dumb non-story, every Ubisoft game is available on Steam. It just means you can buy the game there, not that buying it retail will give you a Steam key. And yes, if you buy it on Steam you will still have to have Uplay just like all of their recent games.
There are settings to minimise your interaction with it so that you just go straight to the game instead of into Uplay's menu system but it will still be installed and automatically start up in the background when you run a game (You can close it once the game's started just like Steam but it won't upload your save to the cloud server).
There are settings to minimise your interaction with it so that you just go straight to the game instead of into Uplay's menu system but it will still be installed and automatically start up in the background when you run a game (You can close it once the game's started just like Steam but it won't upload your save to the cloud server).