There are a lot of people who may think that MJ refers to a tool or a type of tool or a process in music but MJ is known for Michael Jackson. A lot of people still know who he is even those who never got to see him during his peak. He was able to produce a lot of songs that people still sing and play up to now.
People still impersonate him because he just has this charisma that makes him hard to forget. It may have been years since his death but there are still some people who will continue to remember him and play the songs that he sang before.