Not entirely true either. From the link:
> Hixie has said before he’s willing to fully spec the SQL dialect used by [WebSQL]. But since Mozilla categorically refuses to implement the
spec (apparently regardless of whether the SQL dialect is specified), he doesn’t want to put in the work since it would be a comparatively
poor use of time.
Even in that article, the a dev says he's queried the SQLite version in order to detect which exact FT options are available.
The argument for it is basically "eh but it's handy", ignoring the idea of the Web.
If you don't want to just use Sqlite (understandable), and you don't want to write something that is as good as Sqlite (also understandable), then you're going to have a crap database implementation. There's just not a lot of other options there. Jonas' comment just reiterates the lack of choices.
But given the three bad choices, the question does arise: Was IndexedDB really the best of a bad lot? In 2009, a lot of very optimistic things were said about IndexedDB performance, adoption, usage on mobile, developer acceptance. It's been 6 years, and I think it's safe to say that IndexedDB hasn't lived up to anyone's hopes.