> Apparently the Xinhua decided to render "Trump" as 特朗普/Te Lang Pu (
https://www.usatoday.com/story/news/world/2017/01/25/china-d...), instead of doing the American/English thing of "You don't know their language? Well f-you then. No help from us."
Consider a rather unusual (but real nevertheless) Polish surname: «Brzęczyszczykiewicz». Most native English speakers, who are not well known for their patience with long and unusually looking non-native surnames, will instantly give up and shorten it to a mere «B». The most daring and adventurous ones will persevere and will likely arrive at something akin to «Brenshistishkevich», which is neither correct nor easily pronounceable for an English speaker anyway. The few English speakers who are acquainted with Polish, would render and pronounce «Brzęczyszczykiewicz» as «Bzhenchishchikyevich» which is closer to truth, yet it will confuse everyone else who will stick with «Brenshistishkevich» anyway.
Or consider an Icelandic surname of «Þórðarson». We would have «Thordarson» (as a naïve take) or «Thortharson» (somewhat closer to the actual Icelandic version).
Bonus point: Llanfairpwllgwyngyll, a Welsh surname, with the «colloquial» vocalisation of «Lanfarpwilgwingle» vs «Hlan-fair-pool-gwin-gith» (a more truthful rendition).
In all cases, with Brenshistishkevich, Thordarson and Llanfairpwllgwyngyll, we have arrived at the English equivalent of Te Lang Pu (Trump). In fact, there is no need to look at more extreme cases, it will suffice to consider a simple Vietnamese name of «Huy», which most English speakers will pronounce as «Hughey» whereas it is actually «Hwee» – it is still the case of the English Te Lang Pu.
In the case of Mandarin Chinese, the problem is exacerbated by the fact that the Chinese writing script is logographic and can't encode single consonants (single sounds in general, although there are Chinese characters that encode vowelled words, usually exclamations). Secondly (or firstly, in fact), all Chinese languages have a strict rule of a phoneme having the CV(C) structure (Consonant-Vowel(maybe another Consonant)), which makes the CCVCC (i.e. Trump) compound impossible and is completely against the phonetic rules of the language. And many, very many in fact, Chinese speakers neither know pinyin nor speak English. The same is true for many other non-Chinese languages.
It gets a bit better, e.g., in Japanese that, other than the logographic script, has two syllabaries that make it possible to represent Trump as something probably more like Tu-ru-mpu.
> I used to work with a man who's last name was Cao whose name was mispronounced "Cow" […]
Since you also earlier called out «[…] (e.g. do not use "c" for "ts", use the closest approximate for sounds that do no exist in English) instead of maximal fidelity to the foreign language», spelling Cao as Tsao (which is what they do in Taiwan but not in the mainland) is not going help as nearly all English speakers will drop the «t» and pronounce it as «Sao». And, since «ts» is one sound and not two, «Sao» is also the English Te Lang Pu.