Think like me, agree with me
When you're trying to sell your idea, it's natural to assume that the people you're selling to think the way you do. If you can only show them the facts and stories that led you to believe what you believe, then of course they'll end up where you are... believing.
The problem, of course, is that people don't always think like you.
Go watch some videos of people of different political ideologies talking about why they support a candidate other than your candidate. These people are stupid! They can't conjugate an idea, they have no factual basis for their beliefs, they are clueless, they are ideologues, they are parroting a talking head who knows even less than they do! (And those epithets apply to anyone you disagree with, of course). In fact, they're saying the same thing about you.
Same goes for diehard fans of the other brand, or worse, the clueless who should be using your solution, but don't even care enough to use your competitor's product.
If they only thought like you, of course, and knew what you know, then there wouldn't be a problem.
The challenge doesn't lie in getting them to know what you know. It won't help. The challenge lies in helping them see your idea through their lens, not yours. If you study the way religions and political movements spread, you can see that this is exactly how it works. Marketers of successful ideas rarely market the facts. Instead, they market stories that match the worldview of the people being marketed to.
[There's an alternative, one that you might want to think hard about: perhaps you should only market your idea to people who already think the way you do. After all, you're not running for president, you don't need a majority. Screen people by their behavior (what they read, what they buy, how they act) and only tell your story to the people who will embrace it. That's a lot easier to do that than it's ever been before.]