I agree, and see it similarly - I think I said "extracurricular" above. I suppose we'd have to consider Davis Cup, too, although considering that's a group event, it is hard to know how to consider it. But bonus points, indeed.
Yeah, I know. And to be fair to Rafa, I think the fact that he--like Novak and Roger--has won all four Slams on three surfaces is more important than lacking a WTF, but I also appreciate your attempt at objectivity (and we only ever attempt it) about the WTF. And to be clear, even if the lack of a WTF is a sizable hole in his resume, it doesn't exclude him from the "Herd of GOATs." He's in the club.
As a side note, I only casually followed tennis during the 90s and early 00s, so don't remember this, but I wonder how much of a mark on Pete it was considered that he didn't win at Roland Garros? If I remember correctly, after Laver's epic 1969, Agassi was the only guy to win all four Slams until Roger, Rafa, and Novak came along, so it wasn't as much of a "must have" on an inner circle great's resume.
My point being, the Holy Trinity have re-written the history books. I know that's obvious, but 20 years ago the whole idea of a "tennis great" was very different. Before Roger came along, Sampras was considered by many to be the greatest player of the Open Era, despite the "flawed" resume (his relative weakness on clay). The only guy who some considered on par with Pete was Borg, and he had his own flaw: his shortened career (not to mention, his lack of a USO).
Roger set a new standard, and then Rafa and Novak joined him. Going forward, the whole notion of greatness is just different than it was before these three. While no one will ever not consider guys like Becker and Edberg--not to mention Connors, McEnroe, Lendl, Borg, etc--to be all-time greats, the Holy Trinity have created a new "inner circle great" club, of which probably only Rod Laver could be considered a predecessor.
My point being, while the criteria for "all-time great" remains the same--something like six+ Slams and time at #1--the Big Three have created a new category of "inner circle greatness," and I think only Laver could be considered to be in that club, at least in the Open Era.
If we're a bit more liberal about it, we could look at the "Herd of GOATs" as being those player who--at the time they played--were considered at least a
candidate for being the Greatest of All Time (Thus Far, to address
@nehmeth 's unnecessary literalism). So then we have, starting with the beginning of the Open Era, six players: Laver, Borg, Sampras, Federer, Nadal, and Djokovic. I don't think anyone else really qualifies, with everyone else not quite reaching that "possibly the GOAT thus far" status (e.g. McEnroe looked like he was going in that direction in 1984, but then collapsed).
Meaning, this latter approach accounts for the changing nature of the tour, as it seems unfair to judge previous eras by today's new standards. As far as I know (and maybe someone like
@Fiero425 can give more input), no one talked about the need to win all four Slams. I mean, I don't think Borg had that as a top priority, maybe not even Sampras. But now, with the resumes of the Holy Trinity, that seems to be a requisite going forward.