GOTG promotes a lot of fun they are a what you see is what you get group.
You see a giant tree that says Groot, a Raccoon with a foul mouth, a snarky lead in Star Lord, a warrior in Gamora, a big dense oath in Drax. Easy to get to know 5 characters in a wacky fun adventure with good music pumped in.
Eternals is asking viewers to do a lot of work since most of the trailers don't come off fun. It is a giant group of like 8 or 10 never appeared in anything like cartoons or video games. I can't see many kids wanting to view it just because it is Marvel. I want to get excited for the movie like every Marvel movie but I just can't bother learning these characters names and powers when I expect most to die. I am not expecting a sequel and those that survive will be side characters. Probably the wrong way of thinking going in, but it is my current feeling for the movie.