It means whoever is writing is an outsider to Jewish religion. I have never, ever, once heard a practicing Jew use the word “Yahweh”. I find it extremely jarring to read. I feel that if you’re going to talk about somebody else’s religion, you ought to be respectful and use the authentic terms from that culture. In Judaism we refer to this name of God by various phrases, such as “the four letter name” or colloquially HaShem, which just means “the name.” For philosophical discussion, some use the word “Havayah” to discuss this facet of God. If you need specifically to refer to the letters of the Hebrew word using Latin characters, you could write YHVH, but I wish people would stop using the obnoxious and pervasive spelling “Yahweh”. It seems to be used exclusively by atheists and Christians, and often to give the misleading, false impression that the Jewish God is one of many options. Judaism is monotheistic. God is God, end of story. My recommendation is to use the word “Havayah” instead. It refers to the same Hebrew name, and is actually a respectful word used within Jewish religious discourse.