Not every player responded or noticed.
Luffy didn't take the bait because they know they're Luffy and they also know scum are unlikely to draw attention to themselves by fake claimng Luffy, hence why they kept quiet.
Luffy easily could not be in the game.
All three possibilities are in play. Now, I ask again. If you have role information that suggests Luffy is scum it's time to claim it. Because what you are currently arguing is not persuasive enough for me.