Switzerland is complicated. They are not in the EU, but closely aligned and essentially bound to many of the EU rules and regulations via agreements. Whether that applies for warranty or not is not something I know, but it’s definitely possible.

In practice they are at economically if not politically.

They are in the free trade area so most EU regulations regarding goods apply there

Nope, Switzerland is out of the single market and doesn't have a customs union with the EU, but

> most EU regulations regarding goods apply there

In that point you're right.

Interestingly enough Switzerland is part of the Schengen area. So, as others pointed out, it's complicated.