I don't think thats the point being made. Just that this will probably make German cars more expensive, but Britain doesn't make any good cars of their own and so they don't have a ton of other options.
Actually, Britain has a significant automotive industry - the third largest in Europe!
British brands are heavily weighted towards premium, high quality models. Jaguar, McLaran, Land Rover, Mini, Bentley, Aston Martin, Lotus, Rolls-Royce, and others.
There's also significant design and manufacturing presence in the UK for Ford, GM, Nissan, Toyota, and Honda.