The challenge of bringing back Duke Nukem is actually what is interesting about him as a character at this point. Like, at this point, the idea of placing him in an Ion Maiden-like enterprise just isn't 'hard' so-to-speak; it's everyone's natural first thought when tackling the problem: instead of moving Duke forward, move games back to just fit with his ridiculous character. Problem is, that's not interesting, and this local minima we're stuck in of staying close to "old school shooter" mechanisms to ensure it all fits together is getting, well, tired. That's not to say that there haven't been admirable takes on it, with games like Dusk and Ion Maiden being near the top of the list, but all of these kinds of games share one thing in common, and that's that they're all trying to imitate their betters, and I'd suggest that such an open admission is what keeps these games from actually being better, as backwards as that may sound.
Like there's a world where Lara Croft never moved forward to become a more interesting character in more interesting worlds; they just kept her, tank controls and all, stuck in mostly puzzle-driven environs with, uh, disproportional amounts of polygons. And while I don't think the desire to do that is inherently bad, it was more ambitious and more fun to take her forward, re-think some things, and just make better games.
Establishing Duke Nukem as a real and developed character seems nearly impossible. That's what makes it so interesting. You'd have to completely rethink who he is, what he does, and how he does it. So many have offered interesting revisions for him in the past in threads like these: my favorite is probably the washed up action hero with a reality check, but there are other takes. 3DR failed to modernize Duke because they just couldn't find a pathway to make him more interesting and, to be fair, they were stuck in an echo chamber of their own fans who criticized every turn they took to try something new. id Software has proven that they can, at the least, navigate in part fitting old characters and ideas into a new frame. Flying Wild Hog proved that they could take a racist caricature and turn Shadow Warrior into a hilarious 80s style action romp. MachineGames ... I don't think I even need to mention how they turned Wolfenstein into a game about people with a whole lotta heart.
It is possible to make a better Duke Nukem. It's fucking hard, and the people who currently own the IP are utterly incapable of doing it, but if you handed the property to any of these other developers they could do it.
