Worth adding why the two systems diverged, because it is not arbitrary and it explains why neither is likely to change.
Both are aimed at the same organism, and they intervene at different points. One assumes contamination will happen and removes it at the end of the chain, accepting the loss of the natural barrier and compensating with refrigeration. The other tries to prevent the hens carrying it in the first place and leaves the egg alone.
Each has a real cost. Washing requires an unbroken cold chain from packing to your fridge, and any break in it is a genuine problem. The other approach depends on flock health measures being maintained, and it is less forgiving if they are not.
There is a practical consequence for shelf life, too: unwashed room-temperature eggs are generally sold with a shorter recommended period than refrigerated ones, and dates on the box reflect the system they were produced under. So do not apply the dates you are used to from one country to eggs bought in the other.
And if you keep hens yourself: what you have is an unwashed egg with its cuticle intact, whichever country you are in, and the room-temperature rules apply - until you wash it, at which point they do not.