I asked the same thing to Luke Mulks (VP of Business at Brave) about an year ago when search got out of Beta and he "promised" that the behavior from the built-

I asked the same thing to Luke Mulks (VP of Business at Brave) about an year ago when search got out of Beta and he "promised" that the behavior from the built-in ad blocker would be the same as it is any other page. IOW, the ad blocker does not block first-party ads unless you set the browser to "aggressively block ads and trackers".