These two aspects are a bit contradictory and it's something that I don't get. Israel is mobilizing an unsustainable percentage of their population. During the Yom Kippur War Israel ran out of war supplies within two weeks and had to be sustained by massive US resupply effort in
, Soviet did likewise for the Arabs. This time around Israel is mobilizing an even bigger force. Even if at the moment they are not yet moving forward with group operation that many troops being active is eating up supplies at high rate. If this becomes a long war it won't be sustainable unless US again undertake a massive resupply effort. But weather the will and capability is still there after year and half of supplying Ukraine is unknown.
your reasoning is absolutely valid. however, there is no evidence that the considerations driving israel's decision making are rational. the adrenaline rush has not subsided, and reality has not yet set in. the economic cost will be great but as i said, the strategic calculus now is likely that if they dont finish the job here and now, they will have to do this again in the future. the political calculus is even easier, if hamas is still alive and kicking at the end of all this, then they can claim victory as hezbollah did in 2006. the end state has to be the complete removal of hamas from gaza, and since there is no alternative political power in gaza now, it will likely have to come under israeli occupation for some time.
this of course is not even considering potential pushbacks from the rest of the muslim world. of course in theory that is what the US carriers are there for.
at some point the US is going to tell israel to wrap it up. in fact i would not be surprised if the US is secretly opposed to a ground operation because as you said, they will have to foot the bill if that happens.
a big disadvantage for the israelis, which nobody is talking about, is that they did not at all plan for this contingency, so there is no plan they can pull off the shelf to follow. the cost-benefit analysis of each course of action was never explored, so they actually have no idea what they are doing.
for other muslim forces like hezbollah, there is the option of just sitting at the sidelines until such time that israel is exhausted, or public appetite for war goes down. but it seems like they have opted for sporadic border clashes to stay relevant. the calculation here is likely that israel cant afford a two front war. it would be really interesting if syria also joins for real (more than just the pot-shots on golan now).
