Hi Mico!
And what should they write? That they are making the machines that do not serve anything? This is advertising often not supported by any results only opinions of users who managed to settle some health problem. There is no guarantee that someone else with a similar problem will help.
You can read my stories about the construction of electronic devices in the "My R.I.F.E devices" thread. From my experience it results that I do not need a lot of power because for my plasma device in the last version, 12W of power is needed from the mains to be effective. It also follows that it is not necessary to have modulation and a carrier frequency only to know the correct frequency of the pathogen to remove it from the body.
I have recently changed the frequency delivery method to a magnetic (induction) loop and here the power delivered is about 1W to get the effect. These are the results of many years of analyzing the problem, different constructions and, as a result, developing own prototypes.
I understand that people who have a health problem expect that someone will tell them specifically what kind of machine they should buy to remove this problem. There is no unambiguous answer to such a question.

Anyone who wants to sell such devices will use advertising tools to achieve this.