Playing Xbox Series X games on Series S.

Xbox One games can be played on the Series S/X, but Series S/X games cannot be played on the One.

Because on my Xbox series x, it only shows 'Optimized for series x/s' but if a xbox series x version of a game is NOT 'optimized' how would i know if I'm playing a series x/s version of a game?

An Xbox One S is not the same as a Series S. You would not be able to play Series S/X games on that console.

The One version of the game can be played on a Series S/X. The Series S/X version cannot be played on a One.

Well first there is no series s with a bluray drive

Xbox one s does and that isn't a series s

Xbox one games are compatible with xbox one games whenever it is one x or s

Series consoles are just xbox series NOT one s or x

They labeled series consoles that way for a reason to differentiate xbox one games from series games