I finished the Last Dance last night. I think Jordan is still the greatest player that ever played, but there is now way he would have won 6 in 8 years in today's game. Jordan and the Bulls benefited from 4 major factors in the 90's.
1) Expansion - this is the biggest factor, by far. The NBA went from 23 teams in 1987 to 29 in 1995. The dilution in talent around the league was profound, and made it possible for a Championship team that could hold its core together and make smart supporting cast pickups to dominate. Imagine if Alonzo Mourning, Shaq, Glen Rice, Kendall Gill, Nick Anderson, Isaih Rider, Larry Johnson (in his prime), Steve Smith, Rony Seikaly, Horace Grant, Pooh Richardson, Damon Stoudamire, Marcus Camby, Walt Williams, Shareet Abdur-Rahim were all taken off expansion teams and consolidated onto the original 23 teams. Somewhere there would be a few teams that were really, really good.
It is not a coincidence that the Bulls' run starts when Charlotte started to get good and accelerated when Miami and Orlando get competitive. The expansion teams all sucked their first couple of seasons, but when they started to collect real talent, it was diluting the rest of the league, and making it easier for the Bulls to win.
2) Zone Defense - You can breakdown the NBA into pre-zone and post-zone basketball in a lot of ways. The illegal defense rules were ridiculous, and the Bulls were not the only team to benefit. The Jazz and Rockets did too. That said, if teams could help away from the ball in the 90's like they can now, Jordan would have been denied the rock a lot, and had to give up a lot more when he got it.
3) Pre-Euro - There were a handful of good foreign players at the beginning of the Bulls run (Olajuwon, Petrovic, Marcilonius, Divac, Shrempf, Smits), and even by the mid 90's there were maybe 10 that were capable of starting or contributing to a playoff team, and the Bulls had one of the best in Kukoc. Since then, Yao Ming, Dirk Nowitski and Tim Duncan are first ballot HoFers, the Spurs won 5 titles with 3 foreign players as their stars, and the Lakers won 2 titles with Pau Gasol as their second best player. Today, the best player in the NBA is from Europe, and almost every NBA team has 2-3 foreign players that are at least decent.
Europe was not churning out top talent then like it is now, and some of the best didn't make it to the states in their primes. If Arvydas Sabonis played for Portland starting in 1988 like he was supposed to, (before his knees turned to concrete, he gained 50 pounds, and consumed a few thousand liters of vodka) Portland would have won multiple titles. Sabonis in his prime with Drexler, Porter, Cliff, and Kersey would have been unstoppable.
4) Moneyball - Teams would have played Jordan differently if there were advanced analytics in the 90's, and they certainly wouldn't have left defenders on an island against Jordan for 30 possessions a game like they did then.