There’s two big points here. The first is the primary thrust of the article: Americans being more efficient and driving less has created the unforeseen consequence of reducing revenues collected via gas tax to improve and repair our roads. This should be changed so that the tax structure isn’t dependent on a behavior we do want to reduce. Ultimately, a gas tax is not a sin tax, which is why this happens.
The second, implied point of the article is that we don’t spend enough on our infrastructure. Keeping all of our country’s infrastructure, not just roads, will both stimulate the economy and save money otherwise wasted on needless car repairs and expensive water main breaks. Spending money on infrastructure is going to be way more stimulative to the economy than most industry-specific subsidies, though the lobbyists won’t hear it.