Chuck,
I agree with your sentiments and appreciate your contributions, as I am sure the vast majority here do also.
You are right - SNS3Guppy, I believe, was the poster in question. For all I know, SSR could be another incarnation of the same beast.
why not have a forum for private pilots to ask questions and to exchange ideas where Pprune will check out the background of genuine pilots who want to contribute useful advice
A very similar proposal has often been raised regarding the professional pilots for whom this site was, originally, founded. Unfortunately, it would prove every bit as difficult to implement and maintain here as for the professionals (and it's never been implemented).
when there is a problem cull the answers from posters who are trolls.
We try - it's not always immediately obvious who they are, as the "Walter Mittys" can be very convincing for a long time - SNS3Guppy was credible for years.
Please remember that PPRuNe is 100% voluntary - both in terms of the moderation and the membership - and having genuine pilots continuing to contribute voluntarily has much more of an impact on keeping the signal-to-noise ratio high than the efforts of a handful of volunteer moderators.
SD