First, thank you for sharing your perspective.
one useful innovation by providing an alternative system for digital transactions over the web
From my perspective this is exactly proves my point. Blockchain and crypto are solving their own problems.
As for Wakfu. From what I was able to "research" from open sources on this topic, they were blacklisted because they didn't want to fix their payment processing system. Their payment processing was not working correctly, users complained to the PayPal and credit card payment processing companies and this got them blacklisted. And they did added crypto yes, but I don't see how much this actually saved them, as I can find an open financial reports for that.
What I can see is that they are fixed their payment system, somehow (as forums are still contains user woes for payments not processed). If you have more sources on this problem/solution with Wakfu, please share I would very much like to know more.
When your jvm vendor is IBM? I don't see other reasons. OpenJ9 had quite good polyglot vm Platform. I am not sure how well it is now compared to the Oracle GraalVM. As a Singular developer you don't really care about your jvm vendor. Maybe if you already have a lot of IBM specific tooling OpenJ9 will be a nice choice.