Show duplicate files in all search results?

I'm flabbergasted that this is even something that needs to be asked, but how on earth do I expose duplicate files in search for SharePoint online? 

This references something called "Search Center" which appears to be a fully legacy/classic feature. I get that Microsoft moves slowly, but when basic features like searching for duplicates rely on the "Classic layout" there's a huge problem with the entire UX implementation ...  https://learn.microsoft.com/en-us/sharepoint/troubleshoot/search/near-duplicate-items-are-not-listed-in-search-results.

That said, it seems that the default "Search Center" is located "https://tenant.sharepoint.com/Search" with the results page located "https://tenant.sharepoint.com/search/Pages/results.aspx". I've edited this page with either the "Show View Duplicates link" or the "Don't Remove Duplicates" setting (or both). And no "Duplicates Link" or duplicate results are ever shown. 

There is a disclaimer at the bottom above documentation "NOTE You cannot change the site collection search page by using these steps in SharePoint Online. These steps apply only to the Search Center site."

For the life of me how is hiding search results by default even a thing? Why is disabling a non-standard search setting so hard? And why do end users need to experience SharePoint through to VASTLY different UI/UX  just to do the most basic of searches?

Can anyone tell me how to resolve this? Thanks in advance.