Best thing he could have done in 1991 was to look at himself in
the mirror and regret and berate himself for quitting too
early?
Nadal will surely be a contender in 2021.
That's Borg 1991.
But Nadal wouldn't have been a contender in 2021 if he had spent
10 years outside tennis, retiring in 2011 after Djokovic spanked
him couple of times.
I may be off topic here, but Borg, being a boomer, probably never
cared or understood history. Nadal is different. He pays homage
to Spanish royal house, respects tradition, etc.
It didn't help that tennis indeed had entered a new era in Borg
years so you can forgive him a bit for not caring about slam
records.
Similarly we aren't impressed with Tilden 95 match winning streaks
or such stuff.
Nadal is in league of his own though, MPOAT at FO says it all.
1. Nadal, 60 pts (100%)
2. Borg, 31 pts (97%)
3. Federer, 27 pts (19%)
3. Djokovic, 27 pts (19%)