The tradition, which was in effect at the time of the Messiah, of teaching the people that the name “Yahweh” was too sacred to pronounce, and to speak this name was blasphemy...
Exactly. Parts of the Hebrew scriptures written well before then mention the tetragram, but it disappears from scriptures written around Jesus's time.
In fact Islam (7th Century and influenced by early Christianity) has a similar stance. Giving God (Allah) a name is blasphemous because it implies other gods exist.
Also, I note in the Koran, Jesus is effectively pronounced Issa or Essa. It seems to be just an anglicisation to add the "J" to names such as Yahweh, Issa, Ioshua etc. "Jehovah" only starts to appear from around the middle ages.
I am not sure which point johnamos is trying to make. If johnamos is trying to justify the use of "Jehovah", relying on the NWT "translation" to make his point is just a bootstrap argument. If johnamos is trying to justify the use of "Yahweh", well that term already appears in most, (probably all) bible translations in certain parts of the Hebrew scriptures, anyway.