Fuel, excise and sales taxes don't come close to covering the cost of car infrastructure, not to mention the environmental externalities generated.
Fuel taxes, sales taxes, and usage fees (tolls) generate roughly $150 billion per year.
Excise taxes do not even have a good national accounting system and I can’t find a US total number. But, for example, just CA generates roughly $10 billion in revenue from these fees.
Far from not covering the costs, the direct taxes and fees on cars are actually generating a profit.
If you want to talk about externalities you have to account for both positive and negative externalities.
[1] - https://www.urban.org/policy-centers/cross-center-initiative...
[1] https://en.wikipedia.org/wiki/Externalities_of_automobiles Extremely conservative list on Wikipedia. Anyone that e.g. has looked at real-estate pricing before and after a street was made car free and has seen valuations go up by x2-x5 can attest even just the impact on direct livability.