I think we'll be even more embarrassed by fossil fuels, particularly coal and oil extraction, loud, shouty cars that serve no social good, and the concept of just going for a drive. With time we may be embarrassed by all fossil fuel use, but there is some low hanging fruit we should be embarrassed by today.
True, it's really embarrassing but I feel people don't have that much of an attachement to their fosil-fuelled cars and would gladly switch to electric anytime. Sure, there are some car enthusiasts out there but it's more of a sub-culture than a widespread feeling (at least where i'm from). Maybe I'm underestimating Mid-America's love for derby demolition, but I don't know that much about that part of the world. My mom would not even notice if I swapped out her SUV to a Sedan as long as it stays the same color. People are suuuuper defensive about their eating habits. I think you'd have more of an uprising banning soft drinks than banning all fosil fuelled cars. My friends threw in our "gender binary" point of view on gender as another thing our generation will cling on to and be looked upon unfavourably for. Who knows!
People are defensive of changes outside of culture. "I am a vegetarian" is a personal choice; "we're all vegetarians now" is a social shift. In 2004, my wife discovered that wheat gives her eczema. She's an ardent baker; suddenly the constant cracks on her hands and lips made a lot of sense. So she gave up wheat back when it was a few random celiacs and her. Then a whole groundswell of people also gave up wheat (for good or questionable reasons; not getting into that here) and over time things got a lot easier. In 2005 I had to call ahead to the weird bakery that ran out of the back of a tea shop to get enough gluten-free bread to make stuffing. In 2013 I could buy Udi's at the local supermarket. Now, I go out to bars and have to be cautioned by the servers "you should know that one's gluten free" when I order a beer. People like to eat what tastes good and what they can afford. Food is much trendier than you think. Last week I was walking around looking for chocolate wafers for a cheesecake and found myself saying "holy shit, Snackwells" when I saw some of those wretched little devil's food cookies. I hadn't seen them in a decade; when I was in college they were half an aisle.