I've switched on a dark theme for YouTube, and all the pages I've gone to are in dark theme as far as I can see.
However, there's one particular playlist (unlisted if that matters) that is still in the old layout, and I notice the URL has this &disable_polymer=true.
Tried to change it to &disable_polymer=false and removing it completely but it just shows up again.
Am I missing something?
that's standard behavior - YT still didn't implement new design on this. you can remove whole &disable_polymer=true from URL which should bring you desired result.
&disable_polymer=true piece is there for the ability to save an unlisted playlist to your account eg. saving an unlisted playlist should also bring you desired result. more on this topic here: How to play YouTube video list in chronological order?
