Meeting that description would be a material with fractional-spin quasiparticals, and yeah, building a quantum computer would be easy with those. Otherwise, it seems likely we’ll get them in the 30’s, or maybe even late this decade.

That’s not the issue, though. There might well be no helpful algorithms that exist for the thing, outside of research applications like simulating quantum systems. It could only ever be the next big thing for certain scientists unless that fundamentally changes. You’re right, I can’t say for certain that it won’t, but it’s not a good guess.

Broken encryption might be the next big thing, but that’s actually a negative. In my response I put down post-quantum cryptography as a possibility, just based on how I interpret the question.