Sorry for offtopic
On topic - I use both Classic and Dark mode.
I personally found that dark tones are more suitable for laptops, while bright gray gamma is better for big screens.
So on my MacBookPro UI is Dark and on MacMini+external display UI is classic Aqua.
But they are shown only when actual scrolling happens, right? Oh, I've just realized that, for some reason, when scrollbars are always shown, they use Aqua appearance regardless. That is strange.