I think the last high point (in terms of popularity) for the International style was around the redesign for iOS 7. Since then designers have moved away from it

I think the last high point (in terms of popularity) for the International style was around the redesign for iOS 7. Since then designers have moved away from it. It’s still not a revival of iOS 1-6 style skeumorphism, but there is more emphasis on things like drop shadows. Even Windows 10 seems to have backed away a bit from the Windows 8 style (though the Metro design seems more Scandinavian than International). I think responsive design and the variety of device sizes make Swiss design rather difficult. Swiss design is all about using a well defined grid (see Josef Müller-Brockmann). Responsive design, different device sizes, dynamic text size, accessibility features, etc. make this very difficult to implement. Not to mention limitations in technology and APIs (e.g. the difficulty in grid layouts before flexbox and grid).