We talked last week and I asked him what they miss about 'home' now that they've been gone over a year. He said, "Absolutely NOTHING!"
We have a good friend who has worked in Switzerland for the last 20+ years, married a Swiss woman and has 3 kids (dual American Swiss citizenship). When the U.S. wanted to tax his capital gains on his house IN Switzerland, it was the last straw. He was very sad to do it, but he did give up his US citizenship.
Paying taxes to two countries was killing him financially. I don’t blame him for his decision. I most likely would have have done likewise.
BTW, Switzerland has more construction and growth than I’ve seen in my lifetime. When I was there in 2010, their unemployment was 4%, and that was high for them. They have low tax rates and don’t belong to the EU. Now, if everything wasn’t so dang expensive there....