One big problem is that young people don't seem as interested in riding motorcycles (or getting outside their home, for that matter) as they used to. The internet and social media is such an attraction that many youngsters are not even interested in getting a driver's license, much less learning how to ride a motorcycle. My daughter has tried to get her two college-age daughters to obtain a drivers license, but they are just not interested. So she either drives them around or they take a bus to get where they want to go.
However, in congested urban areas, once needing to go to a job, I think more people are riding motorcycles so that they can pass stalled traffic by splitting lanes, which you can do in California. But splitting lanes on a freeway during commute hours can be very risky and requires a lot of experience and understanding of traffic movements. Plus, during winter months you are doing this in the dark and that would really scare me. I have been riding for 56 years and I won't split lanes unless traffic is stopped and vehicles can't quickly switch lanes in front of you as you pass by. But a lot of people are so frustrated by the amount of time it takes to get anywhere, such as their to their jobs or to school on time, that they are willing to take risks that they might not otherwise do.
I have a lady friend (a little older than me) who lives in Vermont and rides all over the country and even she will pass stopped traffic by riding along the shoulder when the temperature is very hot and there is no movement in sight. That is a sure ticket in most states, but they have to catch you first.

Anyway, I agree that selling electric motorcycles is going to require a different business model for future dealerships. Something like Hollywood Electrics has managed, but they have a great location and the owner has the skills, education and knowledge to keep the business open. Those are business qualities that are very few and far between in the industry. H-D dealers won't have any problems, because their legacy IC products and life style sales will keep the doors open. Electric motorcycles will just be a little icing on the cake - provided that they give the technology a chance and don't badmouth it to their customers.