Looking into privacytests.org, the main developer behind it is someone who contributes to Brave source code. He may not be officially affiliated with the company, but it would be hard to ignore any sort of bias towards Brave.
I've been seeing a lot of techy "privacy" blog posts, even here on Lemmy. It's a little annoying when they muddy up the waters like this. People new to privacy will come across them and head off in the wrong direction.
We need more comments calling them out and linking to proper resources. The site linked in this post even has a confusingly similar name to the actual recommended resource:
(And a quick sidenote: privacyguides is the same team from privacytools. There was a name change after the original owner for the domain came back and fought over the project. PrivacyTools is now a paid advertising site, and it is NOT recommended. https://www.privacyguides.org/en/about/privacytools/ )
Edit: while I'm at it, here's the official community on Lemmy
Even Privacy Guides has its own set of controversy, where basically one group completely took over the community from its founder (who themselves wasn't squeaky clean, either).
Tbh I don't really care enough either way. But I would lean a little more towards privacyguide's account of things, while I still don't fully trust their judgement either. I can't remember why now but there was something they were very fanboy-like over which I disagreed with, and since then I haven't been following their advice, let alone their drama.
The article on privacyguides I linked above touches on some of this as well. I haven't read through this one, but seems like the less verifiable one in a "x said y said" situation?
PrivacyTests actually started prior to him joining Brave. Brave contacted him, and used that resource as a kind of checklist, to try and improve their browser. Despite the guy now working there, it remains an independent project.
There is no clear indication of bias, from PrivacyTests, just accusations.
If the tools and tests ARE open source (which they are), they can be checked for bias/cheating. Someone could also expand (fork) upon them to give more of a rounded opinion.
A better defense against accusations of bias is a group or persons transparency.
Simply having an open source methodology and code base isn’t transparency either, since it takes a much, much deeper and more developed skill set to audit both software source code and testing methodology than it takes to raise an eyebrow at sus circumstances.