The fact that the article seems to use it to mean a 25% increase just highlights that TechCrunch has bad writers and no editors.
> A display that’s up to 2x brighter in the sun.
if you click the arrow to look more, it elaborates
> For those bright, sunshiny days, the Super Retina XDR display now reaches a peak of 2000 nits outdoors — that’s twice as bright as before
whereas "up to 2x brighter" ought to mean (according to you, and my wishes) thrice as bright. If you look through the rest of the marketing copy, Apple consistently uses such language.
- My stock went up 100% == I doubled my money.
It’s not ambiguous. Apple uses correct grammar.
“2x as bright” or “twice as bright” is correct. “2x brighter” is not the same. Apple uses both.
#x implies multiplication (from the mathematical notation of multiplication, ×, which looks like the letter X). 1×a = a.
that from the reader's point of view it's always confusing and ambiguous.