One of the things Marvel has always been good at is chasing trends and exploiting it for their own use.
Luke Cage was created during the period pop culture was big on blaxploitation films. They also brought him back in the early 90s looking like he fell out of a New Jack Swing music video, and again in the late 90s when they depicted him as some kind of hardcore gangsta.
Punisher was made in the shadow of Bronson's "Death Wish."
Ghost Rider was brought in twice, once to exploit the "Easy Rider" and psychedelic culture in the 70's, and once again to absorb more of that grim n' gritty comic bux in the 90s.
Shang-Chi was created back in the 70's back when Western audiences were eating up Kung Fu movies. Marvel saw a big pile of money and decided to exploit that. He's had a few, few bit pieces here and there, (usually wheeled out for when more interesting heroes are visiting China), but he's been pretty much a D-list back burner character for close to a half a century.
And the Eternals, I'm completely in agreement with you on that. Hell, until recently whenever I've seen art of Eternals, I always thought it was DC's New Gods. To that end, I'm not not really buying into this - feels a lot like Inhumans 2.0