This just isn’t true, there’s definitely other companies or people out there making subs that work.
These kind of subs are just audio files that HOPEFULLY challenge your subconcious into being a better person and pursuing your desired goal, that’s all they are and sometimes it feels like people can lose track of that. I’ve seen it said a few times that they are simply tools, powerful tools, but still tools to make your journey better.
You don’t mix these things from different vendors because very rarely do people share their scripts (As they shouldn’t, why would anyone buy a sub if the script was just available to download and make yourself?) and the scripts could just be clashing and cancelling each other out. Could you listen to 2 different subs from 2 different vendors which both focused on building confidence? Probably, but why risk it? It would just be better to listen to the same file twice if you wanted more exposure.
We don’t know that any of these companies aren’t putting in “evil stuff”, subclub included (though i really don’t think they are). The question is whether you’d rather trust your subconcious with a company that is dedicated to making good products that sell or a completely anonymous entity on youtube (who are most of the time just kids xD)