Complicated parking

I don’t understand these Compact Car Only signs. Is it me, or did the phrase Compact Car cease to have any meaning since the mid-70’s?

There are a few of these signs posted in my veterinarian’s parking lot, and I never know what kind of car is permitted to park in these spots.

Yesterday I was trying to decide if my Subaru Baja qualified as a compact car. After deciding against it and parking in an adjacent spot, Elysha aptly pointed out that the wheel base of my Baja was no larger than that of the Volkswagen Beatle parked next to me.

Wikipedia defines compact car as:

A compact (North America), small family (European) or c-segment car is a classification of cars which are larger than a supermini and smaller than a large family car. Current compact cars are between 4,100 mm (161 in) and 4,450 mm (175 in) long if they are hatchbacks, or between 4,400 mm (173 in) and 4,600 mm (181 in) if they are cabriolets, sedans or station wagons. Multi-purpose vehicles and sport utility vehicles based on small family cars, which are called compact MPVs and compact SUVs respectively, have become popular since the early 1990s.

Huh?