Travelling somewhere is not the same as living. It’s pretty common among people without immigration experience to have a certain idealistic idea about it, that does not work in reality.

This person lives in a very international city where they speak English at work. For some people it’s not as easy to get to B1-B2 levels while working full time, having children and using English to communicate daily without issues.

In many EU countries requirement for a permanent resident status is just 4-6 years of residency, plus sometimes certain income/language level. And there is always EU permanent residence permit that just requires you to reside for 5 years.