This isn’t a problem of delivery vehicles so much as a problem with city design.
This might work in NYC. Not so much in LA. Most places in the US are not really friendly to bike traffic and urban sprawl is an issue.
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.