I disagree, the idea that Morihei Ueshiba originated a new purpose to martial arts training is, in fact, the most common view in conventional Aikido. That makes it a reasonable interpretation when it's restated without qualification.
No, that is not how argumentation works.
You are just using the statement to press forward your own opinion on an issue that is not being discussed.
It is not a real response on what was actually said before. That makes it invalid. It has nothing to do with agreeing with it or not.