I'm a zealot, but at some level a realist. I don't think we will abandon cars en masse, but I know that replacing even 5% of car travel with cycling (or scooters or walking) would be a huge benefit to everyone. The lack of safe infrastructure is the single biggest thing preventing that.
There is tons of evidence that cycling infrastructure benefits communities--and improves traffic.
Part of the issue with the traffic is that when most of the roads were built, no one had studied traffic. Now that we have road design is much improved, but unless a government has a reason to invest in new road design, it doesn't happen. So it's probably less cycling infrastructure, and more new infrastructure that helps with traffic flow.
Unfortunately, most people don't know a thing about how traffic works, but think they do because they drive in it. A lot of people want more lanes and more parking, neither of which is generally a good idea. What they don't want is change; so traffic circles and road diets (and even just construction delays for something new), despite plenty of evidence that they are both safer and improve throughput (in the right circumstances--that's not a blanket statement), are met with outrage.
A good example in my town: an intersection was redone because it was a terrible design and limited throughput. The construction outraged people because it's a big intersection in town. When it was finished, there's no question that it improved throughput (i.e., improved traffic). One of the roads it served added a second left turn lane and a section of green paint for a bike lane--without taking away ANY lanes from the cars. Now, despite improved throughput, anytime someone leaves their house late and has to wait at the traffic light in a line of cars (which has been a problem forever there), they blame it on the bike lane, which has obviously ruined their commute (despite literally not changing the available asphalt for the cars). It's remarkable.
And yeah, people lose their minds over a bicycle or scooter left on a tree belt, but think their constitutional rights are threatened if someone suggests they shouldn't be able to park their car in front of their neighbor's house whenever they feel like it.
Bwar, your dichotomy isn't far off in the U.S., but for those of us in the first camp, we see lots of other places in the world where bikes are just ordinary transportation for large parts of the populace, and people who wear lycra and ride carbon fiber bikes are the exception, not the norm. For us, we're jealous of those other places, and we just grin and bear it when our friends come back from Europe and talk about how great their cities are, how walkable they are, and how nice the bike riding for all is (not true everywhere, but true in a lot of places). And, we always grin when a friend says, "you know, I rode my bike downtown yesterday, and it was great! I didn't have to search for parking, it felt good, and it didn't take very long." But that comment is almost always followed by ... "I just wish it was safer; that would make me want to do it more."
The idea that scooters and cyclists have anything to do with the rise in pedestrian fatalities is ridiculous. It is 100% due to the way people are driving their cars/trucks. Traffic fatalities in general are on the rise after decades of them decreasing due to safety improvements in the cars themselves. The only reasonable explanation is driving behavior (WAY more distractions in the vehicle). Cyclists may be involved in 5 pedestrian deaths a year (?--it's so rare there basically aren't any studies on it). Cars killed more than 6000 pedestrians last year (total motor vehicle deaths climbed over 40,000 in 2017 in the U.S.--another increase consistent with a steady rise over the last several years).
And Fearless, that looks like a beautiful road, with curves and sidewalks, too, so unlikely particularly high speed. What's the concern--that you'll have to slow down and pass a cyclist from time to time, costing you maybe 15 seconds of your day?