I'm just going on what I've read here but I think the biggest point of contention that others have pointed out is if they don't sign up for Brave's choice of proprietary monetary systems [0], including its own which it/you has a stake in, the donatee receives nothing. It seems you're trying to reinvent the wheel (browser), or rather pre-existing technology, and make a profit off of it when even decades ago a donate button worked fine without another middleman trying to shove their greedy hands between you and the donatee. You understand why this irks some people, right?

And threatening people online to basically shut up, who you view as misunderstanding, you're vastly underestimating the expected demeanor of a CEO. As a user you'd expect me to be frustrated sometimes and complain but as CEO, honestly, you should just answer the questions as it doesn't make you look professional when denigrating those who used to be in your userbase. And if anything, the fact that I among many have these questions and they've ran so rampant and unanswered even on this very tech-related forum reflects at least poorly on your company's PR department.

0: https://brave.com/funding-your-brave-wallet/