As I'm wont to point out, in terms of statistical dominance
Bruguera at '93 RG was clearly inferior only to
78/80 Borg and
08/17 Nadal in the entire OE, and yet Pistol was still able to steal a set from him (while getting fed a breadstick, yes). Well no sh|t, cuz '93 (and '94) Sampras was among the elite few who
won more than 60% of his games on clay, a feat that even these FO notables never pulled off for a single season (minimum 100 games and DC/WTC excluded):
-Champions-
Kodeš
[Gimeno in OE only]
Panatta
Gomez
Kafelnikov
Moyá
A. Costa
[Gaudio w/unrounded 59.6% in '05]
Wawrinka
-
Runner-Ups-
Franulović
Proisy
Pilić
Solomon
Gottfried
Pecci
Gerulaitis
Pernfors
[Leconte w/unrounded 59.7% in '86 (58.8% in CC season proper)]
Edberg
P. Korda
Berasategui
Stich
[Corretja, but w/60.5% in '97 CC season proper]
A. Medvedev
Norman
Verkerk
Puerta
Soderling
Thiem
[Tsitsipas, w/60.3% in '21 CC season proper]
Obviously the earlier names are iffy due to the political squabbling between competing tours, but you get the idea. To insist prime Pistol would lose to anyone even at RG when only he gets to serve is absolutely comical.
Speaking of which/whom:
When will you get it through to your seemingly impenetrable cranium that you don't get to cherry-pick your examples in hypotheticals like this? For the umpteenth time Fed in '08 had by far his worst outing in a FO final (out of 5). Ditto '92 Pete in the QF (out of 4). You can't put forth the absolute best version of Nadal while doing the opposite for his opponent, because just about ANY top player would win such a staged matchup, on any surface. Pit '15 Rafa against '09 Fed or even 93/94/96 Pete in this harebrained scenario of yours and I guarantee you Bull would struggle to win a
game, because
he won just 58.3% in the '15 clay-court season proper which normally isn't enough to earn anyone a FO, let alone vs. an ATG server who would only get to serve against this subpar Nadal.
But let's limit our hypothetical to Raging Bull only, who as you say won a historic 61.4% of his return games at '08 RG. Here are his RGW%s from each of his individual rounds:
F vs. Federer - 73% (8/11)
SF vs. Djokovic - 33% (5/15)
QF vs. Almagro - 73% (8/11)
4R vs. Verdasco - 90% (9/10)
3R vs. Nieminen - 64% (7/11)
2R vs. Devilder - 64% (7/11)
1R vs. Bellucci - 50% (7/14)
Total - 61.4% (51/83)
Sensational stuff indeed, if somewhat less than meets the eye due to that equally historic clunker from Fed.
Now let's look at '93 Bruguera's own FO run:
F vs. Courier - 23% (5/22)
SF vs. A. Medvedev - 50% (6/12)
QF vs. Sampras - 33% (6/18)
4R vs. Meligeni - 50% (7/14)
3R vs. Larsson - 55% (6/11)
2R vs. Champion - 100% (9/9)
1R vs. Leconte - 54% (7/13)
Total - 46.7% (46/99)
Very impressive but clearly inferior to Bull's '08 rampage, right? Except for the fact that Rafa didn't face a single player who
won 60% or more of his games on clay that season while Sergi had to dispatch not one but two of them (Pete and Jim), and
'93 Courier was in all probability the toughest opponent any Open Era champ had to defeat en route to his FO title.
Of course I know you'll never agree on that last part, so let's meet halfway and remove each of our trump cards if you will. This is what the RGW% comparison looks like when you look at the 1st six rounds only:
2008 Nadal - 59.7% (43/72)
1993 Bruguera - 53.2% (41/77)
So still advantage Nadal, but you can see how much the GW% game depends on the opponents. That's why I say
'93 Bruguera would beat anyone but 1978/80 Borg and 2008/17 Nadal at RG.
And Sampras - you know, the same Sampras who would end up with 60.3% of GW on clay that year - still held serve 2/3 of the time vs. that GOATing Bruguera at that very RG and even managed to steal a set. But you're telling me '08 Rafa would somehow break that prime-grade Pistol more than half the time - not to mention that Rafa would somehow keep up his crazy level even when we know for a fact that he won "only" a seasonal 51.0% of his return games that year and also that
service stats have been rising across the board since the '90s and the Sampras serve would be that much more dangerous today. Sorry, but to quote your own words "the numbers don't agree with your assessment."