I remember when I was first learning about settler colonialism, I thought to myself: “Huh, this sounds like Taiwan and Israel” My instincts were correct on Israel, but I never looked too deeply into Taiwan. The fact that the Kuomintang displaced the Austronesian natives is a pretty strong indicator, but is Taiwan really a settler colonial state or are my intuitions wrong?
The theory of Picts being related to the basques and speaking a non-Indo-European language is no longer widely supported in academia. It was likely a different branch of the Celtic language family.
And if anything I would presume a Tyrsenian peoples related to the etruscans and rhaetians lived in pre-celtic/germanic central europe.