Right, it's like criticizing python, or English, for being inconsistent, or "large". Turns out that doesn't matter -- what matters is that the language is useful because it has a wide base of users and libraries, just like SQL does.
Are there really any SQL libraries in the traditional sense (i.e. reusable/composable SQL code with a well specified API)? SQL "libraries" typically focus on hiding the inconsistencies and the abhorrent syntax under the carpet.
And the user base is there, mostly because of the database engine properties and features. The query language itself is just a bad side-effect. And TFA does make a point that NoSQL abandoning the underlying RDBMS model is in fact a regression.