If Chrome disappears, Brave ceases to exist. Brave totally relies on Google developers working on Chrome and do the vast majority of what it takes to build the browser. Brave only does superficial work in comparison. Brave may itself be privacy-focused but only exists thanks to Google's business model which is mostly tracking the world.
So, yes, Brave is mostly funded by tracking since it is mostly Chrome with some lightweight work on top of it.
> Unreliant on Chrome?
Your cookies rely on the flour you use to make them even if they have chunks of chocolate that the flour doesn't have. No flour, no cookies. (Except in this case it's even worse, the cookies is already done, you just add some colors...).
I too can take chromium and put it in my own git repository and change some minor stuff. It will be "forked" and "separately" developed but it would not mean a thing.
You have a strange definition of not relying.
Of course, we can't maintain all of the upstream ourselves, although we wish Google had fewer typists adding bad or marginal things; but neither can Samsung, Opera, or even Microsoft. But if Google stopped maintaining, the remaining Chromium browsers would carry on.
Your comments suggest a lack of familiarity with our GitHub.