They're both problems. If you watch the video you'll see that most delivery vans aren't even half full. They account for less than 3% of vehicles in cities but a third of bicycle deaths. Due to the fourth power law, heavier vehicles do the vast majority of road damage, which we all pay for.
I wouldn't have expected this community to be pro delivery vans instead of cargo bikes. Europe is switching to ebikes because of good regulation and laws. We should also demand better in places like Canada and the US.
Contrary to its reputation, LA is actually one of the most dense cities in the US, and more dense than many European cities where this is already happening. LA is undergoing a renewal of public transportation and biking for this reason.
And yes, the whole point is change how things are now so that it works. Biking didn’t work in many places in Europe until recently. Paris and London has shown that massive bike infrastructure can be built in just a few short years.
You know, I was thinking that the vans having more capacity and greater speed would mean they're hard to replace. But then I also just remembered that our local postal service does use bicycles and small scooters for their last mile deliveries. I can't remember what my postman uses though. XD
The freelancers who do deliveries for the ecommerce sites however, are likely to be sticking to vans or bigger vehicles, since having that capacity and speed is the only way to get a living wage out of what they do.