Yes and you have no way of telling that. Nadal doesn't even have as many french open titles as Borg. He still is 2 titles shy of Borg's no.
Nobody knows how to beat Nadal right now. Borg said he'd play patiently. Nadal said he'd play aggressively. The fact is there's never been a clay court player like Nadal.
That proves nothing, because all it shows is who Borg played in the Finals. The era he played in had stars like Nastase, Connors, Villas, Ashe, Mcenroe and young talents like Wilander, Lendl and then Clay court specialists like Orantes, Kodes, Solomon and Panatta.
Ilie Năstase never made it past the quarters in the Borg era.
Conners was banned from the 1974 French Open & didn't play there again until 1979. He made the semis in '79 and '80, losing to Victor Pecci Sr. and Vitas Gerulaitis.
Ashe never got past the fourth round in the few years he was seeded.
McEnroe was absent in '78 and '79. His best result in the Borg era was the quarters where he lost to Lendl.
Wilander made his famous debut at the French Open in '82, the year that Borg played one tournament.
Borg's rivals on clay were Panatta, Vilas, Kodes, Solomon, Gerulaitis and Orantes. Panatta is the only player who ever beat Borg at the French Open, in the fourth round in 1973 and the quarter finals in 1976.
That some players didn't win a Granslam Title or as many titles can be attiributed to Borg's dominance as well.
Um, that's exactly what Nadal is doing now. The guy has a 154-14 record on clay. He's not only dominating the French, but the other prestigious clay court tournaments (Rome, Monte Carlo, Hamburg) to an extent Borg never did. Clay court specialists can't get a look in.