This is true, but there are a few things which just happen to be measured in this obsolete and arbitrary unit around most of the world, and pizzas and computer screens are two of the ones that can be mentioned in polite society. :-)

I speak very bad Norwegian. I use metric for everything. But once I ordered a pizza late at night in Bergen after a few beers, and they asked me how big I wanted in centimetres and it broke my decision-making process badly. I can handle Norwegian numbers and I can handle cm but not pizzas in cm.

I ended up with a vast pizza that was a ridiculous size for one, but what the hell, I was very hungry. I just left the crusts.

For display (diagonal) sizes inches have become the default unit everywhere I've been to.