A fuel tax isn't effectively a tax on mileage, nor is it an effective tax for offsetting infrastructure costs. An increase in axle weight causes an exponential increase in damage to infrastructure (the American Association of State Highway and Transportation Officials uses a "fourth-power" rule). Increased fuel economy also has unintended consequences leading to fuel taxes under-funding the infrastructure repairs.
You essentially have heavy-duty or commercial trucks that don't "pay their weigh" and hyper efficient hybrids and EVs that don't "pay their way" when it comes to infrastructure costs.
So fuel tax isn't equivalent to a tax on "miles driven," it might be better suited to off-setting air pollution (pure conjecture on my part), but if you wanted everyone to be responsible for the damage they cause to public infrastructure, you would need some weird calculus of axle-weight/mile driven tax.
Or we could decide major roads/infrastructure are an economic public good worthy of paying taxes on.
The difference is pay at the pump or pay via what your car's embedded GPS is reporting. GPS also allows them to know when and where you were speeding, and since Sweden went cashless, they can simply deduct the fines from your bank account. Compliance is irrelevant.
If having a GPS device on your person becomes law, then avoiding the tax by riding a bicycle, walking, riding a horse etc is defeated.
