Highways, however, RELY on federal funding. Without federal funding, the projects don't move forward. At all. Without federal funding, states can't maintain their roads. At all. Many states are already declaring that certain roads and bridges will not be maintained and will just be closed when they are no longer safe. Homes and businesses accessed through those roads will no longer be accessible. This is happening NOW, with current funding levels. And yet you're proposing to let funds dwindle even more and inflation and political whims eat them away. Advocate for this dystopian future all you want, but don't complain when you can't get to work any more when the few roads still open are incredibly congested.
We've already seen this on a state level. Many states have high gas taxes but below average transportation funding because the funds are raided. Pennsylvania, for example, uses transportation dollars for city beautification and then decided to use the PTC to bail out PennDOT and the transit authorities. Massachusetts is well known for diverting funds and letting things deteriorate to manufacture a crisis to justify keeping tolls on the MassPike. New York spends the majority of its "transportation" dollars paying off the debt from past governors pet projects.
As of right now, even if a huge windfall happened, nothing could be done with it because there are no projects ready for it. So what would you do about it, AlexandriaVA (btw, I find it interesting how you chose to name yourself after a municipality some on this forum despise because of its NIMBYISM)? How would you keep the infrastructure maintained and accessible to all?