There is no "road tax" in the UK, is it? It's a fee for polluting, not using the road. I hate that it's being used as an argument against cyclists: "get off the road, you don't pay road tax". This of course also ignores that most adult cyclists also own a car.. Norway have the same issues now. Almost all new cars are electric. You don't pay purchase tax / vat when buying it. Pay less on toll roads. Cheaper to use. Et…
Registration goes toward running the registration apparatus, not into infrastructure. That's another misconception. The other contribution is from fuel sales taxes/excises, and that goes into general tax revenue as well, so is not explicitly set aside for road projects. Negating the potential income from fuel sales taxes, is all the fossil fuel subsidies, what once was 15bil income, after subsidies of 12bil, is now just 3billion in income from fuel taxes. So the money comes in from the consumer, and goes straight out to the fossil fuel industry through industry fuel tax credits. Absolutely bullshit, but it also means there's not much left of that fuel tax income to pay for infrastructure.
https://www.aph.gov.au/About_Parliament/Parliamentary_Depart....
Ultimately a cyclist will pay the same amount of tax, minus the fuel taxes, and get just a scrap of that tax spent back on cycling.