Conversion comparison between users who navigate from autocomplete vs. submitting from the search form

Recently I came across the way Instagram does their search. Basically they give you results in the autocomplete but disable the ability to actually submit the form and be navigated to your traditional search results page. I found this interesting for the fact with millions of possible users or posts, they are confident the user will find what they’re looking for in no more than a dozen results. Is there any evidence that supports that whether users choose more from autocomplete over navigating to a results page?