The only reason anybody is thinking of destroying civilian infrastructure (wealth) is because everybody took off the table the prospect of sending in cavalry and infantry to seize and hold it.
The chances of success of such an action are very low, unlike for air strikes, as it has already been demonstrated by the failure of the incursion attempted by USA one week ago, which resulted in significant US material loss, e.g. the 2 scuttled transport airplanes.
Be careful not to compare absolute sizes of militaries (which matter in a long term, strategic sense) to the number of soldiers deployed to a specific battlefield (which matter in a short term, tactical sense, for that particular battle). Adversaries who deploy large numbers of troops into a small area make them vulnerable (to foreign air power, yes, but mainly artillery). Adversaries like Iran may have staggering military sizes on paper but their ability to deliver significant numbers of troops to a battleground, particularly when roads, airstrips, and paratrooper transports are destroyed first (by air power), is far more limited.
But you're alluding to a separate concern, which is whether the US military has enough manpower for long-term strategic purposes, particularly since we can't do much about the size of adversary militaries before wartime, but can do something about the size of our own.
> significant US military loss, e g. the 2 scuttled transport airplanes
If the loss of two measly planes is ever enough to be a "significant" military loss, then God help us. The military wastes far more, even in peacetime. We should be so lucky that the enemy continues to hurt us less than we hurt ourselves.