absolutely nothing, except that some pencil-pushers with poor understanding of grammar somehow dislike it even though they often can't even identify it correctly.

Language log has been writing about this for so long it's not even funny: https://languagelog.ldc.upenn.edu/nll/?cat=54

Although the best place to start is probably here: https://languagelog.ldc.upenn.edu/nll/?p=2922