My Kingdom for a Fleshed Out World

Before I begin, let me just say that I love D&D, have for years. And despite its flaws I love 5E; its probably the most accessible version of D&D I've played... and I've played a fair few versions.

But... but! I'm sorely disappointed in 5th Edition's lazy approach to fleshing out the Forgotten Realms. There's just not a lot of official, contemporary material available and what is available has been watered down. I've taken to working with 3E / 3.5E worldbbooks because that's the last time I remember Wizards putting out quality worldbooks.

Am I just missing an amazing set of sources? Are there must-haves on a third party site that I may not know about?

Or, am I right in thinking that the current focus on comprehensive campaigns has left those who are interested in a less structured approach scrounging to find good source?

(Perhaps next time, we can chat about the lack of good, official one-shot adventures.)