Regions instead of sidebar columns

AFAIK Obsidian is basically a standalone browser. Websites have evolved in the past 20 years to eschew sidebars. In my opinion I think sidebars are cool and fine in many instances.

So it got me thinking about Drupal’s response to this: Regions. I’d love to see a top/bottom area where I could put the calendar above my text area, or have a list below my file for tags, backlinks, etc.