The French classic car enthusiast organization FFVE, or Fédération Francaise des Véhicules d'Epoque managed to reach an agreement with Paris officials, and hobbyist cars bearing a special sticker will be exempt from the ban.
This means any 1986 and older car can enter central Paris without fear of getting ticketed, as long as they have a Carte Grise de Collection registration sticker. A regular old car will only have a Carte Grise de Normale sticker, which means it isn't allowed in Paris between 8AM and 8PM Monday-Friday; weekends are still open to cars of all ages.
The legislature still overlooks enthusiasts focused on so-called youngtimer cars, which are newer than 30 years old but still hobbyist vehicles – the Mazda Miata springs to mind. The FFVE is still handling the matter, and there is some hope for youngtimer cars to have their own exemption sticker. The idea of the ban is just to get smoky beaters out of Paris, and a well-kept enthusiast car will be more easy on the environment, no matter if it's built in 1996 or 1986.