The far more viable alternatives are raising vehicle duty or just having a mileage charge
No they aren't.
VED, as a static charge, does not take into account the amount of usage. The same model of car will cost you the same in VED every year whether you do 10 miles or 10,000 miles a year. That's semi-acceptable today because we make up the difference with the fuel use. If you only do 10 miles a year you'll use very little fuel, and pay very little tax as a result. If you drive 10,000 miles a year you'll use a lot more fuel, and pay more tax.
The lack of a centralised vehicle energy source means you can't set up stable proxies for mileage charging. It's basically impossible for someone to bypass the current proxy mileage charge of fuel consumption, unless they're using red diesel, because the tax can be collected through the relatively centralised petrol and diesel distribution networks. Even if a local petrol station is willing to bend the rules for some local customers and not charge them the tax, they'd find it rather difficult when their fuel sale figures don't line up with their deliveries!
Relying on drivers to report their mileage gets you into a whole world of trouble. As soon as you create that tax system, you create an entire universe of people doing whatever they can to create fake mileage meters. The bigger the tax, the greater the incentive to do the work. While this is conceptually true for a GPS-based system as well, the fact that a pure mileage-based system is only an aggregate number makes a backup audit more difficult. Under a tracker system, all you need is a random sample ANPR to verify that whatever vehicles encountered did report that they were there at that time. If the ANPR checks roam around the country without warning, then the likelihood of you being able to avoid that GPS positioning audit would be fairly small. An ANPR system cannot tell though that you did more miles per month than you're claiming on the tax form. The only way to do that would be to cover the country in enough ANPR checks that we can start to disaggregate the mileage and locations, and then you end up going back to the world of GPS tracking anyway.
It really wouldn’t be! It’s a huge volume of data with many moving parts. You need a secure accurate GPS unit (with a tested fitting scheme for every model of car),
Every EV has a satnav and internet connectivity. If mandated, car manufacturers will fit the system. With a random ANPR backup audit, any schemes to break the reporting system would be quickly identified.
a secure communication system with the required bandwidth,
Every EV has or will have 4G and 5G connectivity. The network security on top of this is no more challenging than what this very website uses to give you the green padlock. 16KB per kilometre driven is so small the network wouldn't even notice, even across 40 million users. Assuming you're driving at 60km/h, that's a kilometre a minute, or 13m/s. That would be just 208 bytes/s - able to be handled by a dial-up modem from 30 years ago. 4G and 5G has per-client bandwidth six orders of magnitude greater.
For all those times the public highways change route dramatically without the state ever being aware. Anyway, Google learns that it has old mapping data because lots of people who it believes to be driving (based on GPS, accelerometer and gyroscope data from Android phones) start moving around in places they don't have a road recorded.
an up to date charging matrix (got to cope with road closures and diversions....),
The charging matrix would not change dramatically in short periods of time. Joining positioning data against a road cost table is not technologically complicated. It's a SQL join you could do in one line.
a change mechanism for the road map,
There are already processes that entities have to go through to change the road layout. These designs are all computerised anyway. Road departments would just submit them automatically if they made enough of a difference to the network to materially affect the tax system. That only really happens when roads are stopped off.
the charging matrix algorithm,
Busier roads in more populated areas cost you more money. The charging system could be up for experimentation.
a real-time link to the ownership database,
Why? You're just building a table of positioning facts. You only need to worry about ownership once you start generating the bills. The police already have live lookup systems for the DVLA databases in their police cars.
a payments system (including access for those with no internet and who want to pay in cash),
I believe we already have a system of charging people for using their cars. It seems to work fine. You take direct debits from people, like a utility. The few people who are going to want to pay their EV usage tax with cash would do so at PayPoint stations like they can for other utility bills.
What is there to complain about? That you weren't on a road when your car said you were? The likelihood of this, given the sheer amount of data and the way that even rough positioning data can be resolved into an accurate position using statistics and dead reckoning techniques mean there's really not a lot for people to complain about. Complaints happen when humans get the facts wrong - this system would be pretty bang on in terms of always getting the facts right.
a fraud prevention system.
What fraud? You own the car, you are responsible for it. If the car gets stolen, then you already need to report that to the police. Hell, I don't know why you'd want to start stealing cars affected by this system if you know every car is fitted with a tracker!
you said it was simple, but now you are linking it to a massive new ANPR system?
As I said above, it doesn't need to be massive. All you need to do is make it not worthwhile attempting to make your vehicle mis-report its location data. That aim would be more easily achieved by random mobile spot-checks. The threat that there could be an ANPR camera anywhere from Zone 1 up to the Western Isles means no one is going to take the chance. There doesn't actually need to be a live ANPR camera everywhere at all times.
Billing, collecting, and chasing 40m car owners would be a huge operation
If you don't pay your car tax, then the police are going to come and find you with their existing ANPR system.
One that currently isn’t really time sensitive unless the new owner triggers a speed camera
The bills would be generated after the fact, just like utility bills. So long as you report the day and time of ownership transfer to the DVLA, they can have a record of when to cut over the billing period. Even if you're posting in a V5C the bill can be generated after enough days for any such ownership transfers to get through the system ahead of billing. Even then, the actual charge you could rack up in a day's driving is only a matter of a few pounds, so it's not going to break the bank.
Society already knows who owns cars. It doesn’t need to know where everyone is and has been.
Would you support CCTV inside all homes? Would massively reduce the damage on society from domestic and child abuse and if you haven’t got anything to hide then what’s the problem?
There is no expectation of privacy in public. CCTV in homes means violating private space, as would mandatory cameras inside the vehicle. All the system would know about is that vehicle ID X, owned by person Y, was at some position. It would know nothing about the person driving it or the other people inside. Sorting that out is a responsibility for the vehicle owner, unless they report to the police that their vehicle has been stolen.