Really why should some one has to take credit of retiring early and not wining all four. AO wasnt important but US Open was important even in his time. Let me be clear Borg wining 6 RG titles 5 Wimbledons still so special. I still put him above someone like Djokovic on great players list but thats where it ends.Two Slams on Hard Court has always been the issue since the 90s. Although when Laver won them all 3/4 were on grass (one of the reasons I don't consider his CYS too impressive).
1. Carpet should come back.
2. Grass should go back to 90s fast.
And when we judge players historically, guys like Borg should absolutely be given more credit for winning higher percentage of Slams generally contested than guys like Nadal.