The critical problem they’re trying to solve is the spark gap — the premium that is charged for a joule of electricity vs a joule of gas, which exists because the marginal generation today is provided by operating a gas-burning turbine. Making heat pumps cheaper, both at installation time and for operations, is key for mass adoption, which is necessary if we’re going to stop burning fossil fuels.

I concur. I think there’s two good reasons why and one bad one.
Also, electricity costs so much more than gas in the USA that if there’s a gas main, it is often cheaper to run a gas furnace at 70% efficiency.