I had a bad experience when I checked one of my latest sites at 480px on Iphone X.
everything looked good until I turned the display side ways which gives 812x375 res.

This makes the 400 px or 48- px useless for mobile design in xara. Now I have to raise that number to 500 px to not get this issue.

I think with future releases of iphones this will happen again. Who has time to go back then and adjust all the websites done in 400 or even 500 px.?

Another downside of not using responsive design.