You can get a good look at the big acts announced so far at the official site.
For a brief period that was a lot of my life at that point, say from 1987 to 1995 or 1996, I went to Summerfest every year, several times a year many years. Tickets were ten bucks then, but you could win tickets or otherwise get in free in a variety of ways, and then you would have to carefully plot your day so you could catch the best bands. Oh, the dilemma of some of the headliners: Queensrÿche or REO Speedwagon? Joan Jett and the Blackhearts, George Thorogood and the Delaware Destroyers, or Ani DiFranco? ZZ Top or Living Colour? Not to mention the individual stage lineups that ascend from local bands to regional bands to national bands before the headliner.
Although, to be honest, looking at the lineup announced so far, I could have seen the bands that I would want to see in 2021 in 1995. Which clearly means they need a metal and a jazz stage.
