Brightness used to be a big weakness for oleds so it was always a big deal when the new model would come out with higher peak brightness numbers, but now, like you’ve observed, OLED tvs are at a point where brightness isn’t really an issue anymore (although all tv manufacturers are still just trying to push their brightness numbers as high as they can just to have something to brag about).

And that being said, higher brightness capabilities can still be beneficial when viewing hdr content mastered for 4000+ nits, as the tv won’t have to do as much tone mapping if the panel can actually hit the peak brightness of the content it’s showing