always keep in mind the defense:
Jordan rules
There weren't flagrant fouls in Jordan's era. Teams would just knock Jordan to the floor, and the referee's only option was to call a regular foul.
Handchecking
The NBA got rid of handchecking, this was to allow for easier driving to the basket and it free's up the ball handler. In Michael's era, they would double team him as soon as his shoulder dropped and he tried taking it to the hoop. It was legal to stop Jordan with your hands, not just your feet and position. Handchecking helped out less athletic defenders, who could make up for being half a step slow, by using their hands to hold the ball-handler at 'bay'.
Bigs waiting in the paint
In Michael's era, bigs had a right to 'airspace'. Now the rules are as such that bigs can't jump to block a dunk or layup because if they make contact, it's a foul. There was no 3 second rule so teams would clog the lane to take away MJ's 'above the rim attack'. In Jordan's day you could jump from inside of the circle, or wherever you wanted, and as long as you jumped straight up, and not into the ball-handler, it was not a foul. Much more physical brand of basketball was played in Michael Jordan's era.
Also now they allow ball-handlers to carry the basketball. As well as players like Kobe Bryant get more touch fouls now on the perimeter than any single player in the history of the sport. It is a changed game.