I can't imagine an 'all electric' towed RV. They just are not insulated well enough to heat (or cool) well enough. Even propane and a 30 or 35,000 Btu furnace will struggle to maintain a comfortable temperature at less then 32* in a 400 square foot area (8'x40' + slides in round numbers) while my 95,000 Btu gas furnace in our 3000 sq foot home does just fine at below zero F. In our area, many with the much ballyhood all electric home have converted to gas or oil.
Then there is that often unreliable 120VAC power at many older CGs. Our 15K Btu a/c was struggling last week during the just past heat as the local power supply had some voltage dips. Didn't want to run the 13.5 second unit. Throw in a few monster RVs with 3 a/c units and it will get even worse
You will still need a 12v battery for the thermostat and breakaway system though it might tend to be much smaller.
Thanks, but I'll stick with 12VDC/120VAC and propane
Traveling with my DW Susan, a couple poodlepups and our 2014 Montana High Country 343RL, being towed by a 6.7 2011 F250 CCLB using a B&W hitch and OEM puck system