Why the focus on coal? California as a whole only sourced 3% of its energy from coal in 2021, and some regions were at 0%. It only made up 20% of the entire US' consumption in 2022
I'd happily concede that in all locations in California a heat pump will be more efficient when averaged over the entire year. I'm less sure about Winnipeg or Whitehorse, especially if we are looking at shorter timescales. Did jmchphers indicate somewhere that he was in California, or even the US? If he's somewhere very cold, I think we still need to at least run the numbers.
(I should probably also add that I've got a heat pump hot water heater and heat pump dryer. I'm a big fan of the technology---I just don't think it's always the head-and-shoulders winner for all people in all locations at all times.)