Isn't Cuba walkable for the most part?

I haven't been there, but the videos I've seen show that they have a very car-centric culture.

The relatives I've had visit have confirmed the classic cars. It isn't propaganda. It's that they have a lot of cars from the time just before the US sanctions went into effect. A lot of those cars now have weird engines out of trucks, but because they can't get new car frames in easily, they're keeping them for as long as they can.

I don't think there's anything stopping them from importing electric vehicles from China

Nothing, except for the money to pay for them.

It seems like you're living in a dream world where Cuba has a strong economy and great relations with China.