I watched Borg vs. McEnroe, Lendl vs. McEnroe, Becker vs. Lendl, Becker vs. Sampras etc. matches at the YEC in previous eras, and those matches felt 'huge'.
When the big 3 have faced each other in semi-finals or finals at the YEC, it hasn't felt anywhere near as huge to me, as because I said in a previous post, they'd already played each other so often during that year and others in grand slams and masters series events (and sometimes in ATP 500 events as well).
Plus the increased (and IMO extremely regrettable) obsession with 'slam counting' and attitude that regular tournaments outside the slams are not a big deal, has clearly helped reduce the importance and prestige of all post-US Open tournaments in modern times, including the YEC.
It's definitely still a big tournament nowadays, but it's importance and stature has clearly reduced pretty noticeably over time IMO.
Regarding Nadal, I can't read his mind but without even getting to his singles gold medal in Beijing, I personally doubt he'd even want to trade in his doubles gold medal at Rio with his good friend Marc López for a YEC title.