That's not entirely true. SQL has concepts like "tables", "columns" and "rows" which, if your database doesn't have them, is going to make it really hard to make SQL function at all. (SQL assumes a fairly rigid structure)
For example, suppose your database consists of a objects with attributes, dynamically created, which can contains references to other objects, not necessarily of the same types. Maybe there are no "types" at all and all objects are exactly as they come. They may reference other objects arbitrarily.
While you might try to make something that looks like SQL for such a database, but it's unlikely to be practical.
I think NoSQL should be reserved for databases which don't follow the relational model at all, and thus are unsuitable for SQL even if you wanted it to.