Many European languages predate PIE (Basque, Etruscan) and PIE were only a spoken, not written.
I’ve always wondered why it gets so much attention as an early European concept when people had been speaking other languages for thousands of years, doing cave art dating back tens of thousands of years - it’s like history ignores it.
It kind of reminds me of how they treat “dark ages” when there was actually quite a lot going on intellectually.