I think it applies to most STEM fields. I'm a reviewer for several journals in a STEM field (not AI/ML specifically, but some manuscripts do try to apply AI/ML to this field) and the vast majority of authors seem to upload their preprints to arxiv etc.
Social sciences may be behind though as you say, I do not know as I'm not in that field.
Social sciences may be behind though as you say, I do not know as I'm not in that field.