I would love to see a Transformer such as GPT.x that has learned how to copyedit articles.
I am a member of WP's Guild of Copy Editors. We copyedit thousands of articles per year, mostly making routine improvements to the corpus. WP has many bots that algorithmically modify articles, but transformers have advanced text processing to a far more sophisticated level and seem like a better approach.
The basic idea would be to train using before and after revisions where the after edit summary is labeled "copy edit" or some variant. The transformer learns the art and can then be set loose, initially on articles tagged for copyediting. I am sure that Guild members (including me) would love to provide monitoring/feedback along the way to ensure a quality outcome.
This would allow copyeditors to focus their efforts on tasks that the transformer leaves undone, improving the corpus and allowing copy editors a better quality of life.