Drop the speed limit down to 15 mph on all side streets, and some main streets. Leave a few arterial streets here and there.
Delivery trucks can still share the space, not huge semis but smaller ones are no problem, they are infrequent enough making deliveries to businesses that they shouldn't be a huge burden (see: How the rest of the world handles it).
Keep semis on the main streets of course.
For larger arterial streets, separate traffic by size. Honestly fences are cheap and used in other countries, I am not sure why American cities insist on just thin painted white lines. It is not like a fence takes up significantly more space. :/ (Maybe 2 inches extra width, if that?)
Delivery trucks can still share the space, not huge semis but smaller ones are no problem, they are infrequent enough making deliveries to businesses that they shouldn't be a huge burden (see: How the rest of the world handles it).
Keep semis on the main streets of course.
For larger arterial streets, separate traffic by size. Honestly fences are cheap and used in other countries, I am not sure why American cities insist on just thin painted white lines. It is not like a fence takes up significantly more space. :/ (Maybe 2 inches extra width, if that?)