Why is leesin and shyvana nerfed but not vi?

lets face it Leesin, Shyvana and Vi are strong junglers, with 7.0 jungle changes they have become OP, Leesin currently sits at a 50% winrate with a over the top** 33%** pickrate and 20% banrate. Shyvana on the other hand has a 52% winrate with a 10% pick/ban. Here is where the issue is Vi has a whopping 54%!! winrate with a 15% pickrate leading into a 11% banrate.

Riot has stated not all statistics are crucial but the REAL question is why leesin? Why shyvana? Why were these two junglers with a lesser winrate getting nerfed but not Vi?! She is arguably the best jungler currently and will to fill in the gaps when Leesin and Shyvana are nerfed in 7.1. Her winrate will rise, her play rate will rise and her ban rate will rise, does everyone not see the problem here? Its like removing countries like China, Russia, Canada, Uk ect and leaving America as a power, all the little countries are screwed, AKA every other jungler.

TL:DR Does riot not see what will happen leaving vi at 54% winrate while nerfing the other best junglers?

Edit: I checked the patch notes does anyone see where courage of the colossus is getting nerfed in 7.1? Because i don't everyone who speaks of CotC being nerfed is wrong, Vi's winrate will rise. For those of you saying its on the PBE i am talking about patch 7.1 here not a patch months off.