Not sure from where you're getting that $750 billion number, but it looks like an approximation of the IMF estimate of fossil fuel "subsidies" for 2022, which it claims were $757 billion. Problem is, only $3 billion of those are producer subsidies. The rest, $757 billion are how much more the IMF...
... reckons U.S. CONSUMERS should have paid in (non-existent) carbon and other taxes on the energy they consumed. Of that amount, about 55% relates to carbon and pollutant emissions. But 45% relates not to combustion but to driving. Yet those "vehicle externalities" — the social costs of traffic ...
... congestion (mainly wasted time in traffic) and accidents — would have been just as large if all 🚗s on U.S. roads were EVs. They are not externalities, much less subsidies, "to fossil fuels". A more credible, and well-documented, estimate of U.S. FF subsidies was published yesterday by OCI: