In regards to the article, I have to agree. That's not just a comparison between the movies; it applies to the comics, as well. Before Marvel, most comics were about these powerful, usually unrelatable heroes in the same vein as ancient heroes like the mentioned Gilgamesh and Hercules. I say this, of course, a huge fan of DC. They're vastly more iconic than Marvel partly because they've been around longer and partly because many of them are likened to gods. Grant Morrison even went as far as to have a JLA roster comparable to the Greek pantheon (Superman/Zeus, Wonder Woman/Hera, etc.). I think it's also because when many of the familiar DC heroes were created, it was in the Silver Age: where concepts and adventures were more important than character development. Flash, Green Lantern, and others were the same character from each issue.
Marvel, on the other hand, had full-on character development. We saw Spider-Man grow as a character along the way. Ditto for the Fantastic Four. They weren't these unbreakable gods who beat up the bad guys on a monthly basis. They had faults and things you could relate with them. I'll admit that, even as a fan of Superman, he fell into that same trap in the Silver Age. He was relatable when he first appeared because, similar to Spider-Man, he was empowering for those that had little power (Jews, the poor and downtrodden, etc).
DC has certainly made their characters more relatable over the years while Marvel has stopped some character development on their universe in favour of hitting the reset button for new creative teams. But there are still a number of DC mainstays that have little character. Hal Jordan, for example, the prime example of a Silver Age character, really doesn't have much character. Even Geoff Johns' run on Green Lantern isn't memorable for the character or his development (because there isn't much), but the various new colours of Lanterns created and the subsequent wars. Basically, it's just a modern version of the Silver Age formula.
Unfortunately for DC, their very much more powerful characters to Marvel's makes it hard to make movies. Wonder Woman's Greek mythology demands a big budget. Ditto for GL (and we saw how well that worked out). Superman is a great character, but the audience demands threats that he can tackle, which make it hard to make, budget-wise.
Whereas with Marvel, their characters are - for the most part - much more down to earth with smaller threats (in comparison) and more focus on character development. Heck, look at Thor. He's basically Marvel's Superman and what did most of his movie have? Him without powers trying to prove his worth. It was still a great movie, but the fact that you can do that with Thor says something. At least half of Spider-Man 2 was spent completely out of costume, focusing more on Peter Parker, and it was still a great movie. I say this as a tried-and-true DC fanboy, but that's not as easy to do with many of their characters.