I've thought about this a lot. I think its more the sheer oversaturation of "culture" than it is a true lack of imagination. People alive today consume exponentially greater amounts of "culture" (for the broadest term possible) than anyone ever before, and it's not even close.

When tech enables you to experience a movie or a video game or a performer 30 years after the death of everyone involved, in essentially the same fidelity as the day it debuted, "old culture" has a much harder time making way for "new culture." If Star Wars exists, why care about Rebel Moon or whatever that movie was called?

I think the public consciousness can only maintain cognizance and interest in so much, but at the same time creatives are constantly adding to the Culture Pile. But the more tech enables us to hold on to our past, it becomes more and more difficult to move on, and the majority of new stuff goes unwanted and unappreciated. And so the mass market dives into keeping the old alive with reboots, remakes, remasters, and now AI recreations, because that's what people respond to.