Definitive in terms of the greater Trek tapestry. It is the canon answer, the one future Treks tied into the same continuity will abide by. Sounds pretty definitive to me. (although I too prefer J. M. Ford's take on the Klingon Empire from The Final Reflection)
I've benn over this ground enough before. I know B.S. when I smell it and nothing has changed. ENT is its own thing and no one is beholden to it including its stupid contrivances.
Fits in perfectly well with ST09, though, and it's mindlessness.
And "future generations" can ignore this just as I do the way makers of a lot of current Trek ignored TOS.