As far as I know, there are two types of humankind music.

1) OST such as "Amongst the Mighty." 

2) Bgm of specific culture such as "Aztecs Flutes 1" and "Khmer Harp 2."

The bgm of 2) exists in "HUMANKIND™: Music for the Ages". But I couldn't find the bgm of cultures in the industrial and contemporary eras here.
And also, when I actually play the industrial and contemporary ears I have never heard of a 2) type of specific culture bgm. I could only listen to a OST such as 'Amongst the Mighty' that keeps repeating over and over.

Is this a bug or is it intended? Because of this, music's of that eras feels very boring.