Dark mode button

Discoverability or simplicity? Toggle or button?

A toggle switch presents both states at once and shows the user exactly what they are choosing between. However, if a pairing is so synonymous with each other, in this case sun and moon, will the user not understand the choice their making with a button alone? Whilst the toggle may ensure clarity for users that haven't internalised this UI pattern, the button will reduce the visual complexity for all user (even if only marginally) and increase processing speed for all.