WHAT IS WRONG WITH THE FABIANS?

Whenever I talk about the general election here in the UK I receive messages from people telling me that Jeremy Corbyn is a Fabian & as such is not to be trusted.
They seem to attach some ominous misgivings to the Fabian Society.
But if, during a speech at one of their conferences, they are proud to have heard Jeremy Corbyn say this.... maybe the rumours about them have no foundation.
If you have concrete proof that the founding fathers of socialism in Britain are in some way not to be trusted, then link me to it here.
I have been asking but the tumbleweed & crickets are still prevalent on this issue.