YepI can see it being useful for everyday usable classics. Hubnut on the mytube did a piece on a Fiat 500 i think it was. It was very well done.
For some cars though it's all about the engine and converting it to electric would destroy its meaning and value.
That exists in the model world, so you're probably right.It's been around for a few years at least.
IIRC conversion kits were available, but many of the parts were bespoke and the battery life wasn't good. The wider use of battery powered vehicles and as a consequence, their motors and batteries as they get written off in incidents, will hopefully transform the market.
For some cars, it is also the sound of the engine, particularly V8s which can burble. But as currently engine sounds are played through the car's sound systems for some vehicles, it isn't going to take a rocket scientist to replicate this as an after market addition where an electric motor is used.
If they can get the price down to 5k and the government to chip in 2.5k. It could save a lot of these old cars.