I'm debating Darth Bane's authority as the be-all end-all of Dark Side knowledge.
Bane's knowledge of this era is going to be inherently flawed because of the fairly vast amount of time between now and then. So anything he says is subject to his own opinion and point of view. Nothing he says can be taken as objective truth unless it's backed up by some other objective source.
Because it's clear from what Obi-Wan said, that many of the truths in Star Wars is based on one's own point of view.
3. I could bring up any number of other examples.
Don't bother, because any example that doesn't fit into his PoV doesn't count... Just like this game doesn't count, or any other example that proves him wrong. The thread on crystal colors is a prime example of this, every single case that was brought up to prove that alignment restrictions were contrary to lore, he simply dismissed out of hand, claiming they didn't count, or were such a rare case that it still shouldn't be allowed.
He has clearly in his own mind decided that he and he alone is the ultimate authority on lore, so there is simply no point in debating with him.