Today's automotive paints are far superior in hardness and durability to older paints (which technologies are still available). Until the mid-1920s, autos were painted using multiple thin coats of brushed-on linseed oil paint (basically same as the house paints of that time). In luxury models a combination of paints and varnishes were developed. These finishes lasted only a few years in regular outdoor use. This changed with the development of nitrocellulose lacquer (used mid-1920s to 1970s), which coincided with adoption of spray-on application. From the 1930s to 1970s, alkyd enamels and acrylic lacquer were also used (again through the 1970s). Dulling and fading were also a problem with these materials in real-world UV exposure. First in Europe, and then by U.S. manufacturers (in the 1980s), polyurethanes and acrylic urethanes replaced earlier formulations, and are basically what are still in use today, although there has been a steady reduction in volatiles and an increase in UV resistance.
Pigments represent the non-volatile toxic substances in both older and newer automotive paints (as they are in all paint). With the exception of lead (pb), toxic pigments are still used. Even lead pigment is only banned in house paint in N. America and Europe (still allowed in some other paints and coatings), and is still widely used in some nations.
Some manufacturers are now offering auto wraps for some color options, so perhaps all auto paint will become a thing of the past. As lacquer/varnish and paint technologies date back over 6000 years, I expect that it will still be easy enough for someone to replicate old finishes and "accidental stones" like Fordite and Calsilica whenever there is the slightest potential to turn a profit.
A little car paint and steal your kids easy bake oven up in the attic. neal
That thought had occurred to me, too. Getting hard to find the 60 watt incandescent bulbs to power those ovens, though