> Additional highways are at-best a stop-gap for day-to-day traffic, never a solution, due to induced demand [1]. You really need large-scale investments in public transportation for this.
Clearly "improve roads" vs. "improve public transit"...
> How many semi truck drivers and their loads can you fit on a public bus?
You're again arguing against something no one ever said. No one suggested that we should just remove all semi-trucks and replace them with buses. Again, we're discussing where to allocate incremental improvements to existing systems. No one is suggesting doing nothing or, worse, shutting down existing systems.
Using your specific example of semi-trucks, moving more traffic (such as daily commute) to rail lines or buses can actually help semi-trucks as well, by freeing up road capacity for things that actually need it. And additionally, freight trains already make up a fairly large percentage of our freight network (~30%) so rail is actually a great alternative to semi-trucks in many cases.