Swiss nationality is not linked to your birth country, it is linked to lineage. There are second, third, (fourth, fifth, sixth?) generation immigrants in Switzerland that are not Swiss. Conversly, there are Swiss nationals that have never set foot in Switzerland.
I was addressing the implication in the "fact", which is incorrect anyway. One in five of that 27% were born in Switzerland: https://www.bfs.admin.ch/bfs/en/home/statistics/population/m...
I had only heard about rebirth in a figurative spiritual sense.
That's the part they currently don't say out loud. They are getting bolder and bolder though.