From what i gathered from the article they're an indoor proposition, too heavy for outdoor activities according to the author.

It's never going to touch your ears anyway, but your fingers might stay glued to them if it's freezing.

The aluminium part of the ear cups doesn't come into contact with your body while wearing the headphones. There are thick cushions which are in between. Also, their main usage probably isn't for outdoor use, but more towards indoor.

I've got the Beoplay H7 (which are mostly aluminium) and I can report that this is not an issue. Your ears never touch those bits.