It's very hard to understand because you and I were raised from youth to feature the Tetragramaton as a key element of utmost importance. The fact that most all Christians don't see it that way seems to JWs like a deficiency on their part. For them it seems JWs are obsessed with a nonissue. For them, they have grown to address God as "Our Father" as the Christian Bible says Jesus taught them to pray. It's only when the topic is framed as a conspiracy does it take on importance, hence the WT's obsession with the topic since the 30's.
For those who study the topic in detail, it becomes clear that YHWH is an artifact, one of the names associated with the God of the Jews for a period of time in history. The name itself, both its true etiology and meaning, were lost to the Jews long ago. Although the hypothesis that it was understood as meaning "passionate, or blow" is quite attractive: A Nearly Forgotten Hypothesis about YHWH
Perhaps Yah/Yahu was the older form as found in the oldest poetry and songs in the OT and Assyrian texts and not an abbreviation as is commonly (but strangely) assumed. If correct, then etymology and etiology discussions should start here.
Perhaps it was a toponym, a name of a place associated with a deity, Beth-yahweh for example, or like it appears in the Egyptian texts as "land of the Shashu of yahu" in Edom. (I favor this one)
Or perhaps that was once part of a liturgical formula such as Du yahwi sabaot (He who creates the heavenly armies) per F.M.Cross, later shortened to Yahweh Sabaot (found hundreds of times in OT) then just Yahweh with the original context lost and free to be reinterpreted.