I admit there and then that my assumption may be wrong - how is this being unprepared to debate it?

You're not prepared to debate the assumptions you made in the questions you asked in your original post. You're not even prepared to admit you made assumptions. You seem to be starting from the point that all your assumptions are neutral, not up for questions or debate, or even to acknowledge that you made them.

I'm not going to continue this discussion

Evidently you are not.