How common is this kind of connection?

I figured the full question would take up too much of the title.

I am wondering how common it is to have connecting flights in a different country with airlines that don’t originate in that connecting country. For example, flying United airlines to Frankfurt or Munich, and connecting to Bangkok on Thai airways.

Or another scenario where the dominant airline of the airport isn’t a partner. United to Seoul and then Thai airways to Bangkok. Or something like American Airlines to Paris and then British Airways to London.

This is different than 5th freedom flights right?