One major problem with it is that even in those dialects, a double negative can also be a positive, and outside of some semi-fixed constructs that mandate one or the other interpretation in that dialect, the distinction relies things like tone and/or stress/emphasis, which of course are lost in writing. This makes it rather unwise to use in writing, unless context clearly dictates one interpretation.

The more northern dialects are infected with certain negation-related illogicalities too. Consider this New York Times headline:

“All Options Are Not on the Table as Biden Moves Troops Closer to Ukraine” https://www.nytimes.com/2022/02/05/us/politics/biden-ukraine...

which should have been “Not All Options Are on the Table”, since the intended interpretation is

¬∀ option, on(option, table)

rather than the very different

∀ option, ¬on(option, table).

I am never not confused by this.