You seem to have spent your time around sufficiently many unpleasant people that you see their behavior everywhere, even when explicitly corrected. I'm sorry for that.
Could I have independently gone through and rigorously deconstructed my solution? Sure, and we would all be poorer for it. See, there's another, valuable reason people say what I said beside the "classic dismissive nerd thing".
For every person with a question, there's probably 5 more with the same question who didn't ask. By writing down questions like I did, and inviting their answer to be written down, that provides education not only to me but to anyone who reads it after having similar thought.
I consider that sufficiently valuable to create, that I am willing to accept a handful of people criticizing me for "doing the dismissive nerd thing".
So yes. I knew the thing I wrote was wrong, I didn't know why/how, and I wrote it down as is rather than just going off on a personal side quest to come up with some generalized proof. And I would do it again.