France is indeed a lovely country with fantastic roads, sensible speed limits and hardly any traffic jams. It's largely down to a few things:
1. They don't get the rain and freeze that we get which damages roads
2. They prefer to work locally and drive a lot less, though that has probably changed post covid.
3. The population is distributed better
4. It's 50% bigger for the same population.
5. Councils are actually focused on making life better for people, rather than finding new ways to raise revenue.
And the roads are either funded privately or from general taxation.
Although the UK 'Road Fund Licence' has long ago not been used to fund the roads.
I would argue
some all of your points (what did you expect?)
(I nearly forgot that)
1. The rain they get is often torrential and the roads and drainage is built to cope with it, without flooding local fields, rivers, etc.
2. There has been a decades long migration to the cities, especially for the young.
3. as above. Although if you were referring to the distribution and funding of 'non-capital cities' I would agree. There are 'capital cities' for each region, which tends to make the "levelling up" redundant.
4. That makes for more sparsely populated areas, rather than equal population distribution.
5. There are some, what might appear minimal. differences but appear to have great effects, e.g. there is aometimes a 130 kph limit, it's easier to be done for speeding, the cameras are not so well indicated, there are more mobile cameras, there are more spot checks, there is less 'lenience' for speeding. But the fines and points are more lenient. One would expect the latter issue to create more speeding offences, the speeding does occur, but on open roads in rural areas, with practically empty motorways, not in towns and cities, where limits are rigorously observed.
Another minimal point is to include the TV licence with the 'council tax'.