Smart metering often does not transfer between suppliers.
The reason for smart metering is exactly what has been suggested above, due to lack of investment by the private profit-making organisations (so that they can make more profit for their primarily overseas parent companies, who have zero interest in the UK infrastructure, why should they, it's not their country that they are compromising, the UK electrical infrastructure is on its knees and incapable of supporting the proposed roll-out of EV, nor the levels of microgeneration proposed.
EV charging is another minefield. More often than not the car dealer tells you that you can charge the car from any BS 1363 13A socket, which is a lie.
Such suitable sockets have only been available for the last few years and it is impossible to tell from the front whether they are suitable or not.
Additionally, we then have the massive safety hazard in charging from a 13A socket connected to the house supply being used outside with the house earth connected to the vehicle bodywork and the potentially lethal and increasingly common failings of PEN conductors in the DNO networks because they are falling apart due to lack of investment in critical safety maintenance. Then there is the issue with diverted network neutral currents on the supply neutral conductor which is also the earth unless your house has its own earth rod.
Then there are the issues with charge point installers a physical OLEV audit on domestic installations recently highlighted that 1% were dangerous, 8% potentially dangerous, only 21% were fully satisfactory, and 67% required improvement to be even compliant when installed.
The public charge network is even worse, fires and overloads regularly occur because the units are not installed safely, and there are other electrical issues that put the public in mortal danger when using them
I could go on, but, I will finish with when you have your smart meter and your EV, the intention is that if left on charge the EV batteries will be used as a storage reserve for the national grid, as the "smart" charge points which will soon be mandated will take energy from your vehicle to top up the requirements of the grid at times of highest need, to save the private companies investing in their infrastructure, so you may turn up to your car expecting a 100% charge planning on a trip that will use the whole charge and having planned to get to your destination where you can re-charge only to find out that you don't have a full charge and thus are unable to complete your journey in one stint.
A pain if it's a serious commitment.
The above is a fact, the following is my opinion, only those who can pay more will be able to opt-out of having their vehicle battery depleted, thus leaving the rich private profit-making organisations fine, hammering the public purse (think emergency & municipal services because they will be forced to go electric) and the general public unless the rich elite will not be able to afford to opt-out, so once again it will be a means of oppression. Large global corporate organisations already have too much power and influence and are having national governments running scared of legal action or them pulling party funds.
Unfortunately, it is going to take at least one person to die before anything is done, and that is one person too many when it is just to enable companies to make or to have made a profit, and it's immoral and should be illegal.
(we have to reboot it most mornings) 
