And this is where we disagree, my friend. I *do* think it's DC's fault. They're the ones approving writers and stories, assigning editors, etc. And their record with this stuff is, being polite, spotty. I think we can trace Superman's decline, in large part, to DC's choices with the IP. Now sure, there are other factors; some decades have been more accepting and open to Superman's particular brand of heroism while other decades have been more cynical, blah blah blah. But most of the time, most of the fault can always be found with the people in charge. In business, sh*t should always roll uphill.
Now, perhaps it's possible that Clark's setting has become so removed from the modern day that it requires *skilled* talent to handle him well, and average (or below) writers just can't swing it. Maybe that's a possibility. But I really doubt there's much of anything in the mythos that's legit *broken* and more like it just needs some polish and/or an update. Some fresh eyes and fresh angles is certainly in order but the bricks and mortar of the IP is solid, and as you said, more important than ever.