When you browse through a category on twitch, it first gives you a list of streams in your selected language and then simply a list of all active streams in the category, sorted by viewers.
However, as of recently, this is no longer working correctly and it instead just gives you two lists of all streams all the while still claiming to be filtering for your language.

I was going to make a proper ticket for the bug report, but quite frankly, the ticked system is a hot mess and there is no option to report bugs pertaining to filter or search or just general UI functionality (it also doesn't help that accidentially clicking on the wrong subcategory will redirect you to some FAQ page instead) so I'm just gonna hope this way works as well.