Sorry if this comes out sounding like an SAT essay. This topic is slightly too nuanced for my usual free-form style, and I’ve been forced to resort to older techniques to make my ideas come across quasiclearly. I’m not very practised at it.
Anglicisation is the process of altering the pronunciations of words and names as they are loaned into the English language to conform to English’s phonology and phonotactics. While such processes exist in all languages in the world, and have been key in the history and development of English in particular (it being basically 70% loanwords), anglicisation frequently comes under attack in the modern Anglosphere as ignorant or disrespectful of those words’ and names’ languages of origin. One notable example of this is the insistence that “Van Gogh” ought to be pronounced [vɑn ɣɔx].
Little pragmatic reasoning actually exists to support the notion that names must be said as the people who chose them did. That the original pronunciation is the “correct” one is often taken as a given in such discussions, but really, it’s akin to insisting that “Australia” always be said with an Australian accent. I posit that such thinking is itself ignorant of the processes and limitations of language and that all loanwords and names ought to be pronounced with Anglic accents because anglicisation is consistent with descriptivist thinking, makes words easier to understand, and makes pronunciations less likely to be overtly wrong.
To expand on the first point, anglicised pronunciations are actually more correct than nonanglicised ones from a descriptivist point of view. For those who aren’t aware, descriptivism is one of the two primary schools of thought in linguistics, the other being prescriptivism. Where descriptivists seek to understand how language is used and why, prescriptivists seek to promulgate and encourage how language should be used. While both schools are quite common in layperson conversation, I believe that anyone who gives the two approaches sufficient thought will eventually conclude that descriptivism is the only one that makes any sense. The underlying assumption of prescriptivism that there is a correct form of any given language is simply false upon careful consideration. While languages such a French and Lingua Franca Nova have governing bodies and documents that serve to standardise their use, English in particular is wholly decentralised. It exists only in the minds and records of its speakers, and has never remained quite the same from one year to the next. If the majority of English speakers say a particular word a particular way in English, and no single person or entity claims to be the global central authority on that word, then who can say that anything other than that most common pronunciation is the sole correct one?
In other words, what rule exists to say that the correct way to say a word is as it currently is in its language of origin, and by whom is that rule enforced? If [ˈʃæŋ.hɑɪ̯] communicates the correct city in China, then why insist that it be pronounced [ʃɑŋ.ˈhaɪ̯]? The prescriptivist response is usually something abstract and axiomatic about it being disrespectful, or about the residents of the city (who actually say [zɑ̃.hɛ], I might point out) wielding regular control over its pronunciation in English, or about it being just fundamentally wrong. Abstract axioms are no basis to concoct rules for a system that is inherently self-governing, and the reasons for insisting that anglicisation is wrong are therefore ultimately baseless.
Next, and more importantly, words are more understandable to other English speakers when anglicised. Last year, I ran a charity auction for my school where the charity, elected by the student body, was United for Puerto Rico, or Unidos por Puerto Rico. Because I was young and naive at the time, when people asked about it, I said the charity name [u.ˈni.dos poɾ ˈpwɛɾ.to ɾi.ko]. Ignoring the fact that I was slightly wrong (fairly inevitable since I didn’t speak Spanish at the time), this pronunciation proved to compromise the name’s ability to perform a name’s only task: to communicate information. Other English-speakers, not expecting Spanish in the middle of the English sentence, regularly failed to comprehend the phrase even to a meager enough degree to repeat the phonemes back to me.
This was by no fault of theirs; parsing a phrase that contains non-English sounds is an inherently difficult task. Without the established phonology of a single language, there are far too many potentially meaningful sounds that humans can produce for the given waveform to be accurately characterised after being heard the first time. Did that start with an [u] or an [ɯ]? Was that a [wɛɾ], or an allophonic [or]? Anglicising to [ju.ˈni.ɾoʊ̯s pɔɹ ˈpɔɹ.ɾə ˈɹʷi.koʊ̯] just makes it easier to understand. And a word that is understood is the only kind of word worth saying
Finally, and most importantly, those who strive to pronounce loanwords as they are in their languages of origin inevitably do it wrong. A prime examples is one of my favourite YouTubers, Paul Barbados, who—bless his heart—has claimed in the past that “Maori” should be pronounced [moʊ̯.ɾi] (the Maori pronunciation is [maː.ɔ.ɾi]), and that the “d” in “Rio de Janiero” should be pronounced as a [d͡ʒ] (it’s just a [d] in Portuguese). This is because Barby, like most people, doesn’t speak every language in the world. Furthermore, and more rectifiably, they people don’t know the International Phonetic Alphabet. This means that the only way for them to learn the “correct” pronunciation is to listen to someone else giving it, most likely over the internet. This is inherently an error-prone process, and one that is far too likely to result in a pronunciation that is neither standard nor etymologically correct.
It gets much worse when words contain sounds that the would-be pronouncers just don’t know. Rolled “r”s are just the tip of the iceberg when it comes to sounds English-speakers can’t make. Most people who insist that foreign words be pronounced foreignly don’t even realise that there’s something particular about the [q] and [tˤ] in “Qatar”. If you speak a language, by all means, pronounce words from it in that language (with the understanding that you will sound a bit pretentious and potentially incomprehensible). But if you don’t, then at least in my opinion, don’t try to pronounce words in it, as it will likely only come across as more ignorant and disrespectful than the standard anglicised one.
So there you have it. Anglicisation is a perfectly valid and very useful tool that has long been used in the English language and should continue to be used thus. Modern calls for loanwords and foreign names to be pronounced in their original language are based on empty assumptions, encourage less comprehensible speech, and are difficult to execute properly. The correct pronunciation of a word in English is the way the majority of English speakers pronounce it—[væn ɡoʊ̯] or [vɑn ɡɔf]—and any attempt to make people say it otherwise is fallacious.