Two things. There is no system on Earth which tracks, which you can ever, ever trust to be purged. We already have issues with state actors, all over all of our democracies, constantly stepping out of bounds.
They spy where they are not allowed, play tricks with the letter of the law. For example, 5-eyes, where Canada is not allowed to spy on Canadians, and the UK on UK citizens, so each spy on the other's citizens, then hand the data over.
Or recent stories in the US, of the government buying data from the private sector. They can't spy, so they pay the private sector to spy.
I have zero faith that any scenario where data is harvested, that it won't be illegally/immorally/sneakily used. And history, that all important metric, 100% backs up that this sort of thing happens again, and again, and again.
So point #1? There's no scenario where we can ever trust 'track and delete'. Nor, can we ever trust any 'black box' in a car. EG, if we cannot open it, examine it (something highly unlikely in a metering device), no way will I ever trust it.
Number 2? Tolls are beyond impossible. I think you must live in a population dense area, to believe they are viable.
Yet think of rural routes, side roads, or just normal non-freeway roads. There are many 100s of millions of miles of these, and they greatly outnumber freeways. They cost upkeep too.
I often go 6 months without driving on a freeway, where I live. I know many people who drive thousands of km a month, yet are entirely on rural roads.
There isn't even network connectivity, including cell, in some of these areas. Phones. Loads of roads have no power lines, are just 'connect this dirt road to this dirt road', yet see a thousand cars a day.
As a side note, right now, we aren't paying per km. People driving a sports car, get 1/2 or 1/4 the gas mileage of a little smart car or some such. Yet, they both pay the same for gas.
Two things bother me here:
1) The whole reason most jurisdictions have 'tax people when paid', is because many people cannot save, and even if they could, literally have no money left at the end of the year.
If there is some 'pay later' or 'show up yearly, be tolled, and pay' scenario, this won't work well. Not at all. Collections alone is a horrible cost on any service, which costs immensely.
2) We already have odometers, which are theoretically sealed, illegal to monkey with, tied to car value, and with a HUGE history of laws / court action wrapped around them.
Anything can be monkeyed with or hacked, ANYTHING, so my point here is that odometers are already in the car, show distance, and have laws protecting them. And even, already, mechanics fully aware of the punishment for tampering with them.
(Odometer replacement even legally requires setting the replacement to the same as the old, etc, etc, or making an indelible note of it.)
But I also take objection to the government knowing how much I drive. Or when.
Really, I don't think this is much of a problem though. The whole reason Tesla went with electric, is because Musk wanted reliable gear for Mars. Can't use O2 burners there, so H2 was out.
With the recycling costs, slow charging of batteries, this is only a stopgap.
H2 is where we're going, over the next decade. Once that happens, taxation will be back where it was anyhow.
At the pump.