In this case, YC is probably getting scammed and possibly the founders of this startup. But I’m sure if you dig deeper there is plenty of other shady crap too.
I can totally understand being interested in crypto in 2010. It was a genuinely novel use of technology, which seemingly had a lot of potential. But it's 2025 now, and the primary use has turned out to be crime. I mined some Bitcoin back then, and even sold it on Mt. Gox. But these days? Wouldn't touch it with a ten foot pole.
Think of it this way - 500 years from now, will societies still be using paper/polymer notes along with silver/tin/brass alloys for coins, or will they be 100% by then? If digital, would you want sovereign control over your assets via open source solutions, or would you be happy that the government with its closed source systems, made by backchannel private no-contest contracts, controls your ability to pay and get paid?