You’d lose that bet

Not to mention people never pull those handles up but push down to open

Yes

Who cares about the wall? A door handle usually turns down. And even if that thing would turn up the chain would slide down the handle. And even if the handle would pull on the chain the pin wouldn't go out because the chain would pull sideways instead of away from the wall, like the pin needs. And even if the chain just pulled the grenade lose from the flimsy tape the grenade would still just dangle from the chain because you need considerable force to pull out the pin.

Edit: I now realised that it's supposed to pull the pin out when opening the door. Would still need a lot of force.

You want the grenade to go off when they open the door and walk inside, not just when they turn the handle, because then the wall will absorb most of the blast.

Geez, you people act like you've never killed a foe with a grenade boobytrap before.

The arc of the door opening should pull the pin, providing the wire doesnt just fall off as the handles pressed down ofc.