> How has Jai introduce ideas if it’s not even released?

These are orthogonal concepts. Jai can or cannot introduce ideas, and Jai can or cannot be released. As of now, it is in fact so that Jai has introduced ideas, and has been released to a closed group of beta testers.

> How can we claim to know what it did “right” when only a few projects have been built in it?

To judge whether Jai did something right, in my opinion, it suffices to read the documentation and experience someone else programming second-hand and take advantage of its offerings, namely making programming less tedious, more enjoyable, more safe. It appears to me that you set the bar of usefulness or success too high for no good reason.