To be fair, running electric only at slow speeds is still good, because it's slow, stop-and-go driving that benefits the most from electric.
2. i suspect but i have no way to prove... the PHEVs sold in america tended to be way better EVs - there's no similar total fleet emissions laws so no incentive to subsidize shitty/fraudulent PHEVs in the US.
The buyers wanted a petrol car. And they choose to fill with petrol. You need your own garage to make plugging in worthwhile (and avoid getting charging cable nicked). Consumers perhaps prefer to avoid the hassle of plugging in?
In New Zealand there's a visible disincentive of a yearly tax on pluggable hybrids (to pay for road use). In NZ roads are paid by taxes earmarked for that.
It would be better to say that all of the money from road use and petrol taxes are spent on the roads. Those taxes don't actually cover the cost of maintaining the road system.
At which point it kind of becomes moot that those taxes are ring-fenced for paying for roads. Since I've lived here people keep repeating that ring-fenced fact like its some kind of special thing. General taxation and council taxes are subsiding just the road maintenance, and completely paying for new build roads.
Yes they almost did.
Only a few years ago the National Land Transport Fund (NLTF) was almost entirely self-sustaining, funded by road users.
Recently Crown funding (grants and loans) expanded significantly to ~40% of fund income.
But approximately 30% of government transport spending is being spent on rail (to placate voters I think). Before the Land Transport (Rail) Legislation Act 2020, not much we spent by the NLTF on rail.
Currently ~3% of driven kilometres by car use electricity - so as that number increases, BEV and PHEV vehicles will need to have increased taxation. Presumably something like $700 per annum (currently about how much a person driving a petrol car pays on excise tax).
Ultimately it is almost tautological that road users pay for roads, since government spending comes from taxes, and most people use cars. How things get earmarked is just sophisticated accounting.