Fridge is not a good comparison, it's much smaller than any AC unit. But that's irrelevant, house AC is larger than car AC, yet still delivers fridge-like reliability.
Both house AC and a fridge compressors are driven by electric motors. They are sealed inside one housing with the compressor with only electric contacts sticking out. This means they are perfectly sealed and coolant cannot leak.
Car AC compressor on the other hand, is driven mechanically by the engine. This means there is a rotating shaft that must enter the compressor housing. There is a seal on this shaft, but it's a moving joint, so it can't be perfect. This is pretty much the only difference between car and a fridge. Due to it, car AC constantly leaks coolant and it has to be refilled every few years, while a fridge sits there for decades with no coolant loss.
And yes, they can make car AC as reliable as house AC. It just has be an electric-driven AC. So in cars that are either fully electric or have a generator big enough (about 5 times larger than usual!), the AC is just as reliable as a fridge. But in a gas-fueled car it's less fuel efficient, as you have to first convert mechanical energy to electricity and then back again to drive the compressor, imparting conversion loses both times. It simply doesn't pay off, it's cheaper to just have it refilled every few years.