It was very difficult to get any information about the energy output of oldtimers. After a long search I found a reliable source from which I took the information that gave me a very surprising result.
The biggest positive point about a vintage car is the fact that it has already been manufactured.
In Europe, a new car is purchased every 5-7 years on average. Since most of the emissions are produced during the manufacturing process and then "decomposed" during use, the modern car becomes more and more environmentally friendly the longer it is driven.
Yes, a classic car is by far not the most efficient vehicle in use, but if you take a 40 year old Porsche, then you save on average 6-8 times the energy emissions that occur in the production of new cars.
In addition, with the veteran status the car is moved a maximum of 2'000km, more is not allowed by law. This also leads to massively lower emissions.
According to the CEBR study, it was calculated that a vintage car emits about 563kg of CO2 per year, which corresponds to half of a smartphone emission per year.
This is not to say that a classic car is more energy friendly than a modern electric car, but it definitely has its justified right to exist.
sources:
Economic-impact-of-the-HIstoric-Motor-Industry-in-the-UK-final-Dec-10-3.pdf (associationofheritageengineers.co.uk)
Studie: Oldtimerfahren ist halb so belastend wie Handynutzen (watson.ch)