I think electric drive-motor RVs will be coming - but not for a while.
The battery technology is not where it needs to be (long life and inexpensive) to make electric RVs affordable to the public.
A replacement battery for a Chevy Volt is around $2,000 (using the lowest cost per this article) https://enrg.io/how-much-does-a-chev...lacement-cost/
A 40 - 45ft Coach with GVWR around 50,000lbs would need probably 10 or 20 of these batteries.
Maybe after the Tesla semi and similar offerings, have been in service for a while (I think it will take a decade) the price of batteries will drop and the battery technology will improve to the point where an affordable electric RV will come to market.