Why not look at MSC's record in it's entirety? He is revered as one of the greatest for good reason.
In 1996 he won 3 times in a dog of a Ferrari. In 1997 he pushed the Newey penned Williams right down to the final race....
literally 
. In a car not anywhere near the equal of the Newey penned Williams.
In 1998 he pushed Hakkinen to the last race, despite not having a Newey penned McLaren.
His Benenton WDC's where even more impressive for me. Some absolute insane drives by him, which was in the face of better machinery.
There is no parrellel to Vettel.
Vettel is the benefactor of Newey Genius. This is undeniable.
And Seb uses it very well. Again, undeniable.
I will make a football comparison so as you can see more clearly what my view is. Ruud Van Nistelrooy scored a ton of goals for Manchester United. His European record was immense. He scored something like 60 goals at the same or higher ratio than Messi and Ronaldo.
He was an accumulator of goals. But he would be near anonymous when the team didn't perform.
Now you look at Messi or Ronaldo. When those chips are down, these guys come up with the goods more often than not. They create something, by force of will, skill, or by luck or whatever.....something happens.
By looking at how things have been won, accounting for all the factors, Ronaldo and Messi are on a completely different planet to Mr Van Nistelrooy. And that is not a slight on the guy as his record was fantastic.
Similarly, Vettel has a superior record to Senna. He has a better record than any of his current contemporaries.
Yet why is he not revered as highly as Alonso, or Hamilton?