I don't think they are similar in spirit. These other projects are missing the radical vision that is by far the most important and guiding thing behind Kay's group: to recreate all of personal computing in 20,000 lines of code. Operating system and applications. That is so profound that, if they succeed (a big if) it can't help but change the world. Simonyi and the Jetbrains people aren't in the same galaxy.
(I agree with you about it being kind of hard to follow what they're doing, though.)
I think you're missing the bigger picture here. It's not about a specific application, it's about the notion that the way we write software is fundamentally broken. All of these projects agree that each problem domain can potentially see orders of magnitude reduction in both LOC and bugs if custom languages are designed that fit the domain more appropriately than a one-size-fits-all approach that's been the status quo.
(I agree with you about it being kind of hard to follow what they're doing, though.)