The thing you got to realize is that the executive branch does not have free reign to pass whatever they want. To me, the mark of a good executive is their ability to pass legislation. The Biden administration has done a fantastic job in light of such a polarized political system in the United States. Not everybody is going to want the same things that we want. In order to get things passed, sometimes we have to make compromises.
Furthermore, the Biden administrations passing of the Inflation Reduction Act specifically invested 70+ billion into public transportation (specifically rail), and far more into renewable energy production.
Biden has been able to move the meter to the left while still working with conservatives on certain issues. If you’re looking at it from a progressive standpoint, and you might not think they’re doing as much as they can. But please keep in mind that they also have to represent moderates and conservatives of the democratic branch.
Also, walkability would be state/local issue lol.