The purpose is to make a for-profit browser that respects privacy. They’ve tried a number of different approaches, and they’ll probably try more.
I especially like the idea of replacing ads with non-tracking ads with better clickthrough rate (i.e. higher profit), and share the profit with the sites. Ad recommendations could be made from local data that never gets sent to a server. That’s privacy respecting and profitable, but unfortunately they didn’t get enough deals made with content creators to be effective.
And what a CEO chooses to do with their money is none of my business, what is my business is the quality of the product that company makes, as well as the quality of the work environment that product is made in. I don’t like the direction Brave has gone, so I don’t use it. And now that I know iOS Safari has ad blocking extensions, I’ll no longer be recommending Brave to anyone (I recommend Firefox everywhere except iOS, and I recommend Safari with ad block there).