Yes, and there are popular third party analytics platforms that record all activity on a page, which includes not just every key press, but the speed at which it was done, with or without a submission of the form.

Web browsers should never, ever use auto fill unless the user has already entered that information on that domain already. Popular domains that host third party content should never be able to auto fill.

I'm not really sure but I think the behavior is a bit different with autofill. While the browser show the field highlighted, the data is there for _the user_ but the actual form field has not been actually changed and no dom event is fired.