> the best example is the UX of the main sites like car tax
To give you a comparison, in the US you need to go down to the DMV with a wad of forms, get the bits you can't fill in filled in, let someone make up a price, decide you haven't filled a bit in properly, send you away to a different window, get something else filled in, pay a fee for the filling in, hand the papers in at yet another window, pay for the actual registration, get a temporary registration slip, pay for a set of plates to actually be fixed onto the vehicle, pay for the stickers that say you've paid for a plate, all of which paid by cheque at various windows, with no real idea of the total cost up front.
In the UK (where cars tend to keep the registration number they're given on first registration), you go to the DVLA website, follow the prompts for the kind of paperwork you have (reminder letter, V5 registration certificate, V5C "green slip" if you've just bought it that the previous owner tears off the bottom of the V5 and gives you), it tells you how much it'll be per month or per year, you put your credit card details in, and that's it. Paid, done, nothing more to do.
Lots of this stuff is required to be done by US States, rather than by the US Federal Government, and Americans are in general keen to keep it that way, for a mix of good and bad reasons.
So every problem needs to be solved independently fifty times. People who live in continental Europe might have examples similarly because there are undoubtedly things European countries, especially EU member states could co-ordinate and don't. The difference in population between Luxembourg and Germany is even bigger than between Vermont and California.
To give you a comparison, in the US you need to go down to the DMV with a wad of forms, get the bits you can't fill in filled in, let someone make up a price, decide you haven't filled a bit in properly, send you away to a different window, get something else filled in, pay a fee for the filling in, hand the papers in at yet another window, pay for the actual registration, get a temporary registration slip, pay for a set of plates to actually be fixed onto the vehicle, pay for the stickers that say you've paid for a plate, all of which paid by cheque at various windows, with no real idea of the total cost up front.
In the UK (where cars tend to keep the registration number they're given on first registration), you go to the DVLA website, follow the prompts for the kind of paperwork you have (reminder letter, V5 registration certificate, V5C "green slip" if you've just bought it that the previous owner tears off the bottom of the V5 and gives you), it tells you how much it'll be per month or per year, you put your credit card details in, and that's it. Paid, done, nothing more to do.