Reality is the wall you smack into when you are wrong, as KLM inadvertently demonstrates in this tweet. The three combinations are not equal. It does matter which I try to click with. Only one of the three combinations allows the seat belt to function to protect the passenger. If there were a crash, the result of the first two combinations would be “splat.” Here is some nice irony: I am 100% certain that if I boarded a KLM flight and attempted to use either of the first two combinations, they would insist that I revert to the third.
A seat belt buckle is designed to be complementary with the latchplate. One ignores that obviously complementary design at one’s peril.