I am European and my name and surnames would not render. Most English speakers can't even pronounce my name correctly, which bugs me slightly more than the name not rendering correctly in a computer.

But I still don't see this as a problem. Allowing arbitrary encodings, arbitrary mix in an single text stream of right-to-left and left-to-right rendering, homonyms and visually identical rendering of different byte sequences are all a problem, and in particular when any of these are being used across a web or OS interface, where recognizing the intent is quite important.