Have you read the about page on privacytests.org? How is it a Brave ad (and not a Mullvad or Librewolf ad) when it is not even the best ranked?
Let me cite what I wrote above once again, please read it:
"Note: Each test is counted with a value of one in this chart, however each test may not have an equal importance in regard to privacy. It still gives an image of which browsers value privacy and which do not."
I am the OP of this and I do not use Brave and would never touch it.