The J rating doesn't tell you who is a better player, but is meant to tell you who is having a better season. Among big men this year, I have these guys in this order (per game rating):
Joel Embiid 1.14
Anthony Davis 1.10 (was much higher before the trade drama)
Karl Anthony Towns 1.01
Nikola Jokic .99
Nikola Vucevic .94
Rudy Gobert .92
Blake Griffin .91
Andre Drummond .90
I think Embiid and Towns compare to Jokic the same way Davis does. They all appear to be significantly more dominant players.
And then you look and realize that Jokic has the biggest bottom line impact on winning.
The difference in talent between Embiid's teammates and Jokic's teammates is huge, and yet, Denver is still the better team. The gap isn't that large, but they are better.
It is fair to want to see Jokic continue this through the playoffs, and perhaps for more than one year. But so far, he's the best of the lot.
What are you using to determine this? Also, what are you using to determine that Denver is better than Philadelphia?
The Denver Nuggets have won a few more games in a tougher conference. Its really that simple.
The only argument against this is that it really isn't Jokic. Its that other Denver players are better. Its the coach.
I know depth matters, and Denver's bench is better. But it is difficult to swallow any explanation that asserts that Jokic has as good an overall supporting cast as Embiid does, or that win totals are just as hard to achieve in the East.
The Sixers are 7-8 when Embiid doesn't play. Jokic hasn't missed a game, but Denver's win percentage is slightly worse than Philly's when Embiid plays (67.1 vs. 67.7). Per 100 possessions, Denver is only 2.7 better with Jokic on the floor, while Philly is 9.7 points better with Embiid. That is in a large part due to Jokic's average at best defense. The only real way Jokic impacts winning more than Embiid is by actually staying on the floor and not missing games. That isn't to be undersold as availability is often the best bility, but it also doesn't really show who is actually better.
and I do think you are significantly underselling the talent in Denver. Millsap, in particular, never seems to get the credit he deserves. Plumlee and Hernangomez are very good backup bigs. Murray, Harris, Barton, and Morris are a very strong 4 small rotation, plus they have some other guys like Beasley, Craig, Lyles and that doesn't even account for IT4. Depth and health are often the most indicative thing in regular season success. The real talent test is the playoffs when rotation shrinks and starters play more, but even then I think you are underselling the talent in Denver.