On wanting to use the word "Allah" by Malaysian Christians

I don’t have any qualms if the Malaysian Christians want to use the word “allah” or any other words to refer to their god. But, I just don’t understand why they insist on wanting to use that Arabic word instead of any other words with the same meaning that are more relevant to Malaysia such as “god” or “tuhan”.

Now, it is not strange for the Coptic Christians, which are mostly if not all Arabs, to use that word since “allah” is an Arabic word which means “god”.

However, it is indeed very strange that Malaysian Christians want to use an Arabic word to refer to their god! How many Malaysian Christians are Arabs?

To Muslims, the word god “Allah” has 99 other names. So, do the Malaysian Christians want to use these 99 names to refer to their god as well?

Their insistence on using an Arabic word to refer to god instead of a Malay, Chinese, Indian, Iban, Kadazan, Sakai, etc. word is very bewildering to me. Can somebody please explain.

Thank you.