Add home battery to store electrical energy when cheap (potentially from your own solar panel) and use when expensive.
Then let your country / state lower the electricity carbon intensity.
We must electrify
We can do both - switch everything to electric, and simultaneously adopt habits that limit waste of these.
Obviously, don't save electricity by using carbon intensive energy sources, that'd be counterproductive.
I agree with the rest of your comment.
Given that where I live installing a heat pump water heater costs over 20 years' water heating electricity consumption for me, and it would still use some electricity, so the payback period would be even longer: no, thank you.
Every so often I do the calculation to see if replacing my fridge would be worth it. The payback period is about 15 to 18 years for that. A new fridge would have more even temperatures throughout the cabinet and better temperature control, and be quieter, so I still review it every now and then.
Obviously my internal discount rate for investments is over 6.7%.