The theory that cold environments would be more conducive to the development of technologically advanced civilizations was widespread in the 19th and 20th centuries. The argument behind it is that the cold climate would have offered extra challenges to survival, favoring a process of evolution of the society. In the tropics, where "just reaching out" to pick a fruit, people would have been indolent, with no reason to move.
It's a fake. There are multiple examples of advanced cultures in the tropics. The earliest known civilizations have developed in tropical and subtropical regions - the Sumerians, the Egyptians, and the Indus Valley civilization. In the Americas, the mighty Mayans and Aztecs were in tropical regions, while the natives of icy Canada and Patagonia did not reach the same sophistication. In the Pacific, the kingdoms of Indonesia were much richer than those of New Zealand, where it snows every year. And so on: History proves that there is nothing wrong with the tropics.
The "backwardness" of the tropical regions only came about with the Industrial Revolution in the 18th century, which made Europe gain a technological and hence military advantage unprecedented. A revolution born of very specific conditions, which never existed before, in the tropics or in the Arctic. An event that has many explanations - but the cold is not one. And that spread to other European countries not because they were cold, but because they were close, geographical. economically and culturally.