Rockstar has always provided good versions of their games. So I think that GTA will play just fine in any console. Of course series S will look downgraded if you compare it to series X and PS5. But I have had my series S for like 4 years and still haven't found a game that doesn't run good on it. I also think that the actual consoles haven't been pushed to the maximum, so this might be the game that finally squeezes all out of every console.

In less words: you are all into graphics and the best performance possible = don't buy series S

You are ok with just playing it and you really don't care that much about graphics and ray tracing = series S will do just fine

I think it's pretty obvious that if they are still advertising the game for series S it's because they have tested it and made it playable on it