Not so. If anything, it sounds like you've bought the urban myth.
I will concede that the science is a little complicated and that I don't entirely understand it myself, but the facts remain that being inside a vehicle is one of the safest places to be during a thunderstorm. The body of your car (or a train for that matter) may not be a perfect Faraday Cage, but it obeys a number of the principles common to true Faraday Cages which will protect you from shorts in the OLE or even lightning strikes. The reason is because, like a Faraday Cage, the charge will be conducted around the outside surface of the metal structure rather than any differences in potential.
Lightning strikes are very complicated phenomena. Cars and other vehicles may be used as conduits to earth, but the electricity building up in a storm cloud will always take the shortest and easiest path to earth. Damage to road vehicles struck by lightning strongly suggests that the path taken by the electricity is from the cloud to some point on the roof of the vehicle, then down through the metal parts of the vehicle to a point low enough to the ground for it to then arc out from the vehicle directly to earth. Tyres may indeed be lousy insulators, but the voltages in lightning are sufficiently large for the juice to jump many hundreds (or even thousands) of feet through often moisture-laden air, so how hard is it to jump those last few inches.
Unfortunately, most often the juice arcs to earth from a point where the evidence of such a jump is not immediately obvious (e.g. the floor of the car). However, there is evidence of lightning strikes on road vehicle wheels. Now I will admit to being a layman, but I can't understand how lightning would miss a vehicle roof and strike a wheel in preference to jumping those last couple of inches directly to earth. To my mind, the most obvious explanation is that these marks are the "exit wounds" showing where the lightning jumped out of the car to earth.
Wiki may not be entirely trustworthy in regard to a number of things and I would never suggest that anyone takes their word as Gospel, but wider reading shows that on this topic they are at least essentially correct.
O L Leigh