The idea of categorizing countries by their economic and developmental status began during the Cold War with the classifications of East and West. The Soviet Union and China represented the East, and the United States and their allies represented the West. The term Third World came into parlance in the second half of the twentieth century. It originated in a 1952 article by Alfred Sauvy entitled “Trois Mondes, Une Planète”.[22] Early definitions of the Third World emphasized its exclusion from the east–west conflict of the Cold War as well as the ex-colonial status and poverty of the peoples it comprised.[22]

So…

They wanted to replace 1st, 2nd, and 3rd world to segregate countries based on economys…

But didn’t want to say that’s what they were doing, so picked a random name that doesn’t make logical sense?

Yeah, this is definitely a .ml thing