Not sure if posted already but:
"We presented "The Simpsons" in 16:9 aspect ratio at launch in order to guarantee visual quality and consistency across all 30 seasons. Over time, Disney+ will roll out new features and additional viewing options. As part of this, in early 2020, Disney+ will make the first 19 seasons (and some episodes from Season 20) of "The Simpsons" available in their original 4:3 aspect ratio, giving subscribers a choice of how they prefer to view the popular series."
Early 2020, eh?