"They're not adapting a novel" is NOT THE SAME as "this is not an adaptation".
Don't pretend that was what you were saying. Because even if you were, that's an absolutely asinine point to make that was never in dispute to begin with, since no one claimed they were adapting a novel. Ever. Anywhere.
And nobody ever said "this is an adaptation like the Lord of the Rings" OR "this is an adaptation of a complete story written in books".
No one. Anywhere. Ever. Said. That.
You can call it that if you want, but that doesn't mean it's NOT an adaptation. Those are not mutually exclusive categorizations.
Since those do not exist, it can't be. Which is why no one ever claimed it was.
But, again - this is NOT the same as saying "this is not an adaptation". Which is what you did, repeatedly.