you don’t need emersion heating for space heating, but you will likely need a hot water tank for water heating for showers, etc
“not enough heat in the air” is nonsense, heatpumps are standard issue kit in Scandinavia
we barely burn any oil in the UK. Total installed capacity is ~370MW and is basically never used - see https://electricityproduction.uk/plant/oil/
** The coal plants are nearly gone too, we do burn an absolute shit load of gas however, and that definitely needs reducing.
Heatpumps are not a one size fits all solution, and they are very expensive, that much is true.
There’s a few issues with what you’re saying
Heatpumps are not a one size fits all solution, and they are very expensive, that much is true.