Don't let your nostalgia cloud your judgment. Marketing and manipulative techniques have always been a part of pop music. Back then it was just payola and taking advantage of Billboard's policy about songs only being to chart on the Hot 100 with a physical release.
The funny thing is everyone keeps bringing up Jennifer's "I'm Real", as some beacon of the remix, when in fact, it was one of the songs listed in the lawsuit against Sony for being involved in payola
How many of MJ's #1s have features or are remixed?
How much does a man who sold 29 million copies of one CD in the US alone really have to do to get his song to #1? You tell me!
Not to be crude, but you can't even compare the eras we're living in. For starters, with the highly segmented audiences of the '80s, having a major hit within one genre was often enough to top the Hot 100. So for a crossover success like Michael Jackson? Well, no wonder he hit #1 time and time again.