How long have they been debating the Observable proposal? 4-5 years?
And all this while some other HNers are saying that the browsers are too complicated and its so sad that there won't ever be completely new independent browsers... :)
That said, does a native observable actually buy that much performance-wise? If not, then perhaps an addon library is better. Once a library makes it into JS, it is there forever. That's a big risk when decent libraries already exist.
I don't know, but it should.