Let’s consider USD as a foreign currency to simplify matters.
The cost of hedging USD into CHF is roughly equal to the difference in interest rates of USD and CHF.
In mid 2022 the difference in interest rates was 3%, and historically, CHF has appreciated over USD by 1,5% annually (source). Assuming these dummy figures, we lose 3-1,5 = 1,5% by hedging USD into CHF.
Here are the historical interest rates, excuse the rather sketchy plot:
The higher rates are for USD (source).
It seems that the difference in interest rates has almost always been well over that the historical 1,5% appreciation of CHF over USD.
So, why would I want to drag down the return of a USD bond by as much as 1/1,5% with hedging into CHF?