It does seem like one difference here, then, is that the theory is now in the hands of people with tools and knowledge to scale it much bigger and longer than anyone previously could. This could lead to it finding frontiers instead of just new people discovering an old thing.

Kinda like how neural nets have existed since like the 80s but only more recently have we had the computational resources to actually make them do something more interesting than fit to a complex math equation.

Or 3D graphics, where the math existed long before computers could render them, and then eventually they could render images, then later it resulted in Doom, and 3D animation, and things have exploded in that space since then.

Or how the first computer programmer existed long before the first computer but programming didn't really take off until well after the computer existed.

I don't know if Wolfram has something groundbreaking here. Maybe he has, maybe he's wasting time. But from reading that paper, it's clear that if this is something, it's something that requires a scale that isn't realistic for humans to explore on their own without tools to automate it. It's possible that it requires a scale that even computers today can't get close to, maybe they never will. Like, for example, if they do find the rules and try to run a simulation smaller than a galaxy, would stars even show up at that scale? Planets? Black holes? Having a galaxy the size of ours and others we see might depend on having a universe as big as ours, otherwise it doesn't have enough variation to result in structures this large, which then might make it look like the real rules aren't what we are looking for.