He was cancelled by the establishment. The sales make that VERY CLEAR. He became a threat to the powers that be when Thriller blew up and he became bigger than they anticipated. From BAD on, the sales sink like the Titanic. Dangerous was selling like hot buns! And then Evan C(hild) Handler comes on the scene. He never recovered from there, didn't stand a chance. Invincible was completely ignored, even by the fans.
Thriller: 70 million copies.
Bad: 35 million copies.
Dangerous: 32 million copies. This album would have outperformed Bad and maybe even Thriller if it wasn't for the fake ass allegations.
HIStory: a lousy 20 million copies. Even if you include Blood on the Dancefloor in the sales it's still only 26 million.
Invincible: a pathetic 8 million copies sold while it's one of his best albums.
Invincible didn't have the success of the Dangerous album because it, no let me correct myself: HE was boycotted. Michael had been under attack ever since the BAD album for being too rebellious. Because as iconic Thriller might be, it is not his best album and Dangerous should have topped it in an honest world.
But then again, we can tell he is still being shadow banned to this day, unless you believe the views on YouTube are even close to accurate. Thriller gets a billion views every Halloween, gimme a break...