[Question] how do websites block reader mode and is there any way around it?

Hey all,

I like undistracted reading and very much enjoy the reader mode feature that my web browser has. I am using Samsung Internet (mostly because it has a great dark mode and adblock extensions).

I have noticed that some sites, like BBC News are able to block reader mode somehow. For example when I try and visit this article: https://www.bbc.co.uk/news/extra/bskbb4rmae/inside-north-korea

The reader mode button doesn't even show up in my browser. Is there any way to force reader mode? I just want text and don't need fancy scrolling/floating image elements!

Thanks!