Not a fan of Kitchen Sink setting, I just don't think it's actually conveys the essence of the settings well.
You know what the biggest, most lore intensive, "Kitchen Sink Setting" is? Earth. "Kitchen sink settings" reflect the complex cultural and social interactions far batter then a setting with extremely tight themes, that don't interact with different cultures and stuff.
Take Theros, it's a fun setting, but the lack of an fantasy Egypt, Persia, Macadonia, Libya, Asia Minor, Rome makes it off, because Greek mythology & history involved other civilizations, cultures, geographic locations, and heck sometimes other cultures Gods even. It's woven throughout Greek Mythology and History and culture.
So having a culturally monolithic Theros feels like it's missing a huge part of Greek essence.
You don't have that issue with fantasy Greece in FR, Chessenta has tons of interactions with other cultures, Mulhorand, Turmish, Unther, Tymanther, etc...,
I think I will call "kitchen sink settings" Multicultural Settings, its more accurate.