Problem here is if we take out Federer/Novak/Nadal we don't get some other worldly manic Murray. He was driven by those guys but for sake of argument these would have been his opponents in the 8 Finals losses:
2008 USO: Roddick, probable loss.
2010 AO: Tsonga, a toss-up
2011 AO: Berdych, hard to predict but Berdych would beat Murray later that year in Paris in 3 sets and lose in 4 sets at the 2012 USO. I guess we give Murray this one but it's not a slam dunk.
2012 WMB: WIN
2013 AO: Ferrer or Berdych. Okay yes.
2015 AO: Wawrinka, no.
2016 AO: If Berdych, yes, if Nishikori, probable.
2017 FO: Thiem, toss-up.
So I'm looking at 4 Slams there for sure and maybe 2 more. But this is in a world where I've taken out 3 players. As good as they are, that creates a whole other host of issues. Plus there's never been a player with literally nobody challenging them as much as Fed haters want to make it so, Roddick, Safin, Hewitt, Nalbandian, Davydenko did exist. Other things would come into play.
If I just get rid of Novak/Nadal as Murray's true contemporaries, he's looking at maybe 6 more Slams MAYBE.
I also love how the OP makes it seem Wilander/Becker/Edberg faced nobodies? They played eachother first off, and Lendl is indeed an ATG.
Becker's 10 Finals: Lendl x3, won all. Edberg x3, won 1. Sampras, Stich, Chang, Curren.
Edberg's 11 Finals: Becker x3, won 2. Courier x3, won 1. Sampras, Wilander, Cash, Chang.
Wilander's 11 Finals: Lendl x5, won 3. Cash, Leconte, Noah, Vilas, Edberg and Curren.
So what the hell are you talking about?