He was just amazing.
Despite being the most championship winning driver, surpassing even Michael Schumacher in F1, his driving style was just unbelievable as he got the car more sideways yet in control than any other driver as evidenced by only having few crashes.
WRC will look like the post Senna F1, with Ogier and Latvala being the good-but-not-the-best-drivers winning because their car is better kind of Nigell Mansell in his Williams.
If we add the fact that VW only promotes motorsport to make its road cars look not THAT troublesome.
Now everyone knows most modern VWs are made with lowest-bidder quality parts, specially those for the American market.