The domain registration date doesn’t tell anything about the amount of effort put in it. I usually register the domains of my side-projects only when I’m at 80% done; otherwise I would buy dozens of domains I would never use.
If you want to help orgs who have come to the conclusion they need to diversify to EU services, it does not mean you have to have come to the same conclusion! Also, it's not the same kind of dependency if you get or buy something one-off from a website like this, as if you build your org on top of a single platform/jurisdiction.
They didn’t explicitly point to hypocrisy as the thing that makes it “unserious.” Actually I think a lot of serious projects are a little bit hypocritical, a little bit of hypocrisy is often the cost of contact with reality.
In this case it isn’t even clear where the hypocrisy comes from, though. It’s a service for looking up other services. Does it even handle any PII?
The domain registration in this context is just proof that the website doesn't have any community value. As for the amount of effort, I took a look at the HTML source of the page, and it looks like the person who released it doesn't really understand the technology he uses, even on a website level.
My opinion is therefore that this amount of effort is not nearly enough to hold our discussion here.