So, then you must have a pretty shitty heat pump too because a reliable heat source shouldn't need a backup like that. I've seen a lot of fossil fuel furnaces that had no electric resistance backup but every heat pump I've seen has some kind of backup, which shows how much faith people have in their relative reliability.
Please read his post again until you understand it. Heat pumps are more efficient than resistive heat, but they are limited to a range of outside temperatures. When the outside temperature drops below that range, the heat pump stops producing anything and resistive heat is your only electrical option. It has nothing to do with the "reliability" of heat pumps, its just physics and economics. The goal of a heap pump is to heat inexpensively with electricity. I think my $50/mo charge just to be connected to the natural gas (nevermind usage) year round is much shittier than the heat pump option, and will happily replace my furnace with a heat pump (plus resistive coils for extreme temperatures) and disconnect my gas next time the furnace dies. And both options are way cheaper than the insane fuel-oil prices of the oil furnace I had in New Hampshire.
In "mild" regions like Ohio (presumably stretching across the whole US at that latitude), heat pumps have plenty of months of heating to do, since the temperature is below 70 degrees for about half the year. The temperatures only drop below 0 for maybe a few days in Jan-Feb. This makes the heat pump a bargain, especially with cheap midwest electricity.
I don't know how wind chill impacts heat pumps but I recall seeing that get below -60F before.
Wind "chill" helps, because the heat pump coil is colder than the wind, so it's actually "wind thawing". And this is exactly why heat pumps stop working at a low cutoff temperature - because the coil is no longer colder than the wind.