The English rules of pronunciation are the cause of the differences in saying Nikon. This bad habit goes back many decades when Nikon was the preeminent photography 135 film camera manufacturer in North America.
In English, if a vowel is followed by a single consonant followed by a vowel, the first vowel phonetic is the ‘long’ form. So the letter “i” is the long form “eye”. However because Nikon is a name, it should be pronounced in the short form as it is intended by the owner of the name, “nik-on.”
In English, if a vowel is followed by a double consonant, it is pronounced with the ‘short’ form.
In English, there are rules or habitual ways of putting stress on a multisyllabic word that are different in different languages which can lead to mispronunciation as well.
In English, there are many spelling of words that bear no resemblance to how the word is pronounced. There’s a famous example given in an old spy-thriller movie because the foreign agent mispronounced the name Tucson on a ship (referring to the city in the state of Arizona). I can’t tell you the correct pronunciation; that’s classified as it’s the only way we naïve Canadians have of identifying foreign agents! If a generative AI program is based on a foreign language, it’s likely going to be revealed by its failure to read back English properly that it correctly spells.
There are many words that fall into this category. My favourite university class was Linguistics, not because it was so valuable, but because it was fascinating.