How can we trust in reviewers on Youtube & WordPress which do not declare their conflict of interest – are not many of those paid promotional reviewers?

We can see countless YouTube demos, product reviewers and testers on YouTube and WordPress. But after our experience with the Pinephone and Libreoffice we turn into the negative about those. There where testers which tested LibreOffice on the Phonephone and Fedora and all kind of applications. Did reviewers receive products for free to do their …