What limits demand for cars is that people can't afford them, not that they don't want them. But since by my assumption everyone is working twice as hard, including the buyers, there should be demand to match the supply.
Or that they already have them? In the U.S., isn't the ratio of eligible driving population to drivable autos approaching 1? So, twice as many cars would likely not find buyers and drive down prices a lot.
Sorry if I'm missing the bigger picture stuck on this specific detail.
(Of course, if you think about this carefully enough, the distinction between "more" stuff and "better" stuff falls apart.)
monetary cycles typically manifest over an eighteen month period. i.e. the increase or decrease in Fed policy would impact demand directly likely no less than a year. the only way to dramatically alter this...i.e. to actually get people to wake up and work twice as hard takes drastic currency action.
this is all undergrad economics