our theater has tile at first, but the actual thing is carpeted

A true home theater meant to have the best sound quality will have all 6 sides of the room in the most sound absorbant material possible. No dropped ceilings, no hard floors, and ideally, soundproof drywall. You want the sound to stay in the room. Stone floors will bounce the sound and make it echo. Go with thick carpeting.

Marble tile? That’s acoustically unsound. That was just a silly sentence. Ceramic or stone flooring will add to both echo and ambient sound. Two negatives in one idea, in my mind that makes it a bad idea. The tiles only pluses are easier to clean and long wear life. You mostly sit in the theater room so long wear is a very minor factor. As for cleaning, you only clean the mess you make. None of which is nearly as annoying as someone shuffling heels on a stone floor.