I can see the thinking behind it.
Gas boilers are as efficient as they will ever be, and in getting this far we have ended up with the flawed, unreliable condensing boilers of today.
You can't make further efficiency savings at such a small scale, so have to move the carbon emissions to a larger scale process such as a power station. If you then use an electric heat pump domestically you have a much lower carbon system already, even more so if we ever manage to bribe convince someone to come and build more nuclear.
None of this is an easy retro-fit, as said, so we need to start building houses that can cope with it now.
Many countries have developed district heating systems where a number of properties are heated by a more efficient CHP setup, for example. Shame we don't talk to our neighbours in this country let alone share a heating system with them!
I have been watching an office block near my workplace get converted to flats over the past year or so. They took out one big boiler, mounted 30 odd gas meter cabinets on the outside wall, then ran ugly gas piping around the outside walls to each flat individually, then loads of boiler flues appeared in the walls. madness, but the path of least resistance / cost for the developer. A CHP system and / or large heat pump would have been perfect there.
Developers will always take the cheapest route that will satisfy building regs, so the only thing that will promote change is to force their hand.