[crdoconnor]

>No one would argue that SQL is bad because some implementations are Turing-complete

They do actually. Though when people do say that it tends to be phrased "keeping business logic in stored procedures is a bad idea".

People argue that all the damn time.

Accidental turing completeness usually signals a design flaw somewhere (would you also consider it too controversial to argue that C++ templates mentioned in your link are nasty and people complain about them a lot?).