If I’m understanding correctly this is just Notion reimplementing the now-common (though of varying quality) "Tab Groups” feature that many web browsers have added in the last few years, but in this case they’re adding it into their App. I agree it has value, it’s just funny to see features that are already widely available in web browsers being reimplemented in dedicated apps that are themselves largely web wrappers, when those same apps (Notion, Fibery) can already be used in web browsers that already have these features…
I know, there are advantages to the apps, so reimplementation of such features may ultimately be necessary. The duplicated effort just makes me a little sad.