Apple has a 100% monopoly in the app market by running the only AppStore available for iOS devices, and that store review guidelines specifically prohibits use of any other web rendering engine but WebKit 
> 2. Microsoft's antitrust fine was for forcing OEMs to not include any competing browsers (Netscape) on threat of losing special pricing.
That's not the only lawsuit they faced. There was EU case that forced MS to make a special installer  for alternative browsers.
I really can't perceive the meaningful difference between these cases. And I believe it's about time to force Apple to allow installation of alternative app stores, from where users would be able to install all the apps they want, without being handcuffed by device manufacturer.
iOS with a 13.4% global market share as of 2019 does not even come close to monopolist status. While I'd like to see iOS forced open as well, there is currently no legal method to do so.