They're not gonna stop it, they just won't support it.
Israel uses an absolutely insane amount of ammunition per day, by any military standard. Well beyond of what they could afford if they were on their own, and it's well documented that the US supply line is the only thing that keeps them going.
Aside from their utter disregard for civilian lives and the
war crimes inevitable collateral damage here and there, they're so terrified of losing soldiers, that they don't hesitate to take down a whole block if shots came from there or Hamas militants were seen by throwing at it everything they have. There's
an article on the Guardian where demobilized IDF soldiers describe how this one-sided massacre is proceeding.
If the US cut their support, which remains to be seen, and given its tactics/stockpiles, the IDF has effectively no means to carry out a major (and futile) offensive on Rafah. Not for more than a few days.