The federal government massively under funds the federal highway system.
That said, Road maintenance is not a government power issue. Road Construction might be if they need to seize land.
The calling out of roads is a red herring, Road account for a infinitesimal part of the budget, even the so called "build back better" plan has very very very little money in it for roads and bridges (about 3% of the spending)
To focus on that as an example of government being weak is ridiculous and completely miss understands the role and scope of government in the lives of everyday people.
If the government privatized all the roads would people that support this argument then claim we are in an stateless society because the government no longer builds the roads...
We can agree that the government is terrible at maintaining roads, however I do not view that as an example of government weakening, it is an example of government incompetence. Incompetence is universal and all encompassing for all government programs
But that still means the issue is insufficient government strength, though right? Simply at the local and state level rather than the federal level. Perhaps you can reframe it then as a power misallocation, but it still means some government is not powerful enough to get things done.