I suspect that a lot of the targets around things like EVs ,heat pumps etc are more to encourage people who are planning to replace things to consider getting the more ecologically sensible versions than to force anyone's hand. People can only spend what they have, so insisting that everyone forks out £30k for a bottom of the range EV, or £15k for a heat pump just won't work, and people won't stand for being told they can't have transport or heating and hot water.
Whether this approach will work is anyone's guess. It might nudge things along and improve developments in the newer technology, I suppose. We will need a new boiler in the short-medium term. The plan is to hang on as long as we can to the old one, but to replace it with a gas one before it's too late, so that with luck we will avoid the need for a heat pump before they are cheaper, smaller and more efficient. The same applies to cars - we currently have a diesel one that has an Adblue system to reduce emissions, and will put off replacing it until we absolutely have to, in the hope that by then there will be a better infrastructure for EVs. Even then, we might buy a second hand car that runs on petrol or diesel, as they won't be outlawed for the foreseeable future.
