It appears that Google strongly recommends providing a separate URL for content that's fitted to a user's locale:
https://www.seroundtable.com/google-locale-aware-geo-language-pages-19780.html
However, if you look at a site like YouTube, You can see that content (ie: the recommended videos) changes according to locale without a change in the URL.
Is YouTube not following Google's advice here? Or is the situation different since they only change the recommended videos without actually changing the content of the page (eg: the text and layout)?
I have a similar situation with a marketplace website where I'd like to change the recommended products according to the locale (locale is very relevant for the recommendations for my specific case) using the accept-language header. The general layout of the page and the text is no different, but the recommended products shown (including their captions and pictures) will vary. I wasn't planning on changing the URL for the page though. Should I?