Imagine there was a society in which blue eyed people are referred to with blee/bler pronouns, and green eyed people are referred to with glee/gler pronouns, and one day someone from that society saw a brown eyed person and had no idea whether to categorise them as blee/bler or glee/gler
Early Proto Indo European genders were if things had agency/was animate/acted on the world or not. Was pretty much him and it. A car would be a him because it moves around. Same with a river or a weapon. A rock would be an it. A rolling boulder though becomes outside context, since now he’s an animate rock that has enough agency to kill you. You get enough of these inconsistencies and the language just loses the original plot and you just have to memorize it points to Germanic and romance languages