Not a pro but I'd like to point how that privsec is part of the PrivacyGuides/GrapheneOS mob. I don't want to put them down in any way but that group causes a lot of drama. They are
Tommy_Tran/B0risGrishenko and moderator of r/PrivacyGuides.
Accusations have been made about them and by them regarding other privacy advocates. None of that has anything to do with the quality of the post, but all sides of that drama seem to be very stubborn and immature when it comes to criticism which is a red flag in my book and takes all credibility away from them and suggestion they would make.