GL/GA was a pioneer in social relevance for comics. That's hardly faddish nor trendy since they started the darn thing.
But even there, GL/GA can hardly be considered to be innovative or a trend-starter.
The notion of superheroes giving a plug about greater society in general was created by Marvel, not DC: The Marvel people told anti-racist parables as far back as the "Sons of the Serpent" story by Roy Thomas in AVENGERS in 1966 (this, in an era where entire southern towns had memberships composed of the KKK; antiracism wasn't the impossible to disagree with cliche it is today), the Harry Osborn drug addiction story in Spider-Man, Englehart's Captain America becoming "Nomad, the Man without a country," Richard Nixon revealed to be a super-villain (!), the "ban the bomb" subtext of KREE-SKRULL WARS, the environmentalism inherent in Namor, among others.
And let's not forget the Roy Thomas/Englehart use of the Squadron Supreme, who represented a universe that was pure leftist conspiracy theory: in the Squadron Supreme Earth, Nelson Rockefeller was president. That's the 1960s/70s equivalent of an earth where Kenneth Lay is president.
Placed into this context, GL/GA is a latecomer instead of an innovator. In 1974, If GL/GA came out at Marvel, nobody would have noticed.
Here's a question, just to satisfy my curiosity:
Is there anybody whose personal politics are conservative/right-wing who actually enjoyed GL/GA? And why?
Heavy handed political views that one does not agree with can ruin a book; for instance, I for one, as a liberal/progressive, cannot enjoy Steve Ditko's fascist fantasy MR. A (STARSHIP TROOPERS without the sense of humor, charm, or satire) or the Ayn Rand subtext of Frank Miller's work, for example. Then again, it may be the case that some works with right-of-center themes that I
can enjoy (LENSMEN has frighteningly jingoistic anti-Union sentiments and eugenics theory, but I nonetheless can appreciate it as a well-told adventure science fiction novel) because they "work" for reasons apart from the fact you either agree with the theme or you don't; they are successful as stories in and of themselves.