What specific things are wrong with my installed copy of Brave

I use manjaro linux and I installed brave using the AUR repo. I keep hearing stories about how Brave is just another ad tracking software like Chrome. What I don't understand is why, like specifically.

Because I downloaded Brave from here. The code for Brave is here. I can build and install Brave and it will be the same as from AUR right?

Ok let me list my questions:

1. If the sourcecode for Brave is open and is all I need to compile and run the software then where's the tracker. The code base is honestly to big and high level for me and my professional abilities but I'm not that great of a programmer, I'm just really good. If there are ad trackers or adblock-blockers then I should beable to see it in the code right? I just need help actually seeing these lines of code.
2. I've used wireshark to monitor Brave in isolation and I couldn't see traffic that I would disapprove of. It is also very realistic that I just don't know how to recognize.
3. Just because Google maintains chromium doesn't mean that chromium browsers have to track you. Chromium is opensource and it shouldn't cost much to comment out trackers. So wasn't this already done? And if not can we actually see the lines of code that track us?

Really what I'm looking for is help coming to the conclusion that these browsers are that bad for me myself.