Ah, okay. I think we just have a different idea of what we consider world-building To me, it's really building a world within this cinematic universe where some of the stories SHOULD'T be stand alone entires. It should build off the previous entry, all living in one self contained world.
I also enjoy what you're talking about though too, the little references that remind us, yeah this story is pretty much a stand alone but it still lives in this world. Though I would still say that MCU still does that the best as well. The sheer number of easter eggs in those movies are massive. Flash does a decent job of it as well, though I think they could even have more of the little crossovers. But Flash and Arrow have still done a very solid job of it.