In most countries, roads are funded substantially by tax on petrol and diesel. Every electric car is a vehicle using the roads and paying nothing towards them through that channel. As adoption grows, the revenue falls, and governments are deciding what replaces it.
The options
Distance-based charging. Pay per kilometre driven, tracked by odometer reading or by device. Fair in principle, administratively complex, and raising privacy concerns if tracked continuously.
Annual charges for electric vehicles. Simple, and it charges the same regardless of use, which penalises low-mileage drivers.
Charging tax at public chargers. Easy to collect and misses home charging, which is most of it.
Congestion and cordon charges. Target the roads under most pressure, and are politically contested every time they are proposed.
The transition problem
Introducing any new charge on electric vehicles slows adoption, which most governments are trying to accelerate. Waiting until adoption is high means years of falling revenue. The timing is genuinely difficult.
What is likely
Distance-based charging in some form, phased in as electric share rises, with privacy handled by reporting totals rather than routes. Several jurisdictions are piloting it.
The uncomfortable part
Fuel tax was invisible – paid at the pump, folded into the price. Any replacement is visible and will be experienced as a new charge, regardless of whether the total is the same. That is a political problem more than a technical one.