Well the topic is car A/C and indeed if the outside temperature is 45C (113F), and the air conditioner only produces a difference of 20C, and your target is 22C then you’ll fall short of that by a few degrees.

Also with car A/C (or indoor spaces which take in a lot of direct sunlight), hotter days tend to be the result of greater insolation. If direct sunlight is hitting your skin on a clear summer day it has a significant warming effect which you would want to offset with more ambient or active cooling.