So an event loses its status when non-slam winners have won it? Mkay.ATP Finals just don't suit Nadal. They should rotate the surfaces.
ATP Finals are not a deciding factor in any ATG debates. It's an 8 man competition at the end of a long year. An anomaly. Much derided as an exho.
Davydenko, Tsitsipas, Dimitrov, Corretja, Zverev, Nalbandian have won it. Great players, not a slam between them.
Don't you think that's a little bit tendentious? First, you mention three guys who are still playing and perhaps could win a slam. Besides, at the same time I could mention lots of players who have won (multiple) slams and (multiple) ATP Finals meaning your statement is sort of empty.
I'll never understand people belittling the importance of the ATP Finals. Nadal could have won it already. Just because he didn't, doesn't mean he sucked playing it. His record is above average! And I'm quite sure he and his team really want to win the Finals, because they know it's an important event.