The “air support” isn’t support, because they haven’t made a serious push into Gaza yet. And even if they had, they’re not killing many Hamas fighters. Many of them will be in the vast network of tunnels, which no amount of US-supplied munitions can reach. Even the deepest penetrating bunker buster we have can barely reach those tunnels, and as far as I’ve seen in news reports, we haven’t provided them any of those because we don’t have many to begin with due to their specialty use. For that matter, I don’t think Israel has bombers capable of carrying them anyway, since they weigh over 27,000lbs per munition.
So all that bombing is doing little except killing civilians.