This is a plausible sounding line of thought but English-language sources are rarely consistent about it. In particular, Western European languages, especially French, often get to keep their accents even though they are meaningless to English speakers.
Compare, for instance, how many places will write "Côte de bœuf" but "nuoc mam". German, Spanish, Portugese, and Swedish are other languages where I often see "weird letters" and diacritics left in, even in English-language publications that don't do the same favors for other languages.
That said, it is possible that SCMP is consistent about this so I don't want to call them out as hypocritical without checking.