The actual transactions must all still be transmitted, so this "compression" is actually a way to avoid transmitting transaction data that has already been received by the other side. Bitcoin already does this and while maybe xthinner is better (I don't know) its absolutely not a 99X improvement over standard bitcoin. The problem with the bch people was that they were reckless and dishonest, not that they didn't occasionally create interesting things and have good points. It was a community that was problematic, but still contained some people doing good work.