Gergiev is a superb conductor.  His video of the Brahms Requiem is a wonderful thing.  So far as I know he has not persecuted anyone for their sexual behaviour, and he has made some excellent Tchaikovsky recordings.  (Tchaikovsky was very probably gay.)  

Are his views about the laws concerning gay sex perfectly satisfactory?  Maybe not.  Neither are the Pope's.  Just a few short years ago, Obama was against allowing gays to adopt children.  So let's not start a little inquisition.

I suspect that a lot of the folk sounding off care little for music but enjoy expressing moral indignation.  If the conductor's political views trouble you, stay home.  But barring extreme cases we shouldn't vet musicians for having correct moral or political views. 

This seems like another case of people who prefer moralizing to critical appreciation.  Being a really good critic of literature or music is very hard.  Moralizing about the artist is much easier.