As for spotify, that was also the point I was trying to make i.e. React was made so facebook can ~~poison the minds of the youth~~ help people share stories, Svelte being made by someone who did dataviz for NYT really shows.
Should say at this point that despite my love of Svelte in principal I still would actually probably build an app that used a react-like framework to glue svelte components together as I'm not a huge fan of a lot of the aspects of svelte that have scope wider than a component.