You've in fact heard lots of reasonable sentences from conspiracy theorists, if you replace the nouns. I think it's less reasonable to believe in ZOG than to have the opinion that Gamergate appeared to be more about childish mockery and hatred than the more weighty concept of journalistic integrity. By the logic you're implying, we can't accept that anything is any more or less than exactly what it's most well-spoken proponents try to present it as.

A conspiracy theorist can say reasonable things, however this exact thing is a circular argument: conspiracy exists but our proof doesn't look convincing exactly because it is conspiracy.

There are no generalizations in my comment which you implied.

We know gamergate was a conspiracy because someone found the IRC channel where the conspirators were conspiring.

The proof of which existed only in form of a picture posted by 'someone' who (mildly speaking) was deeply involved in the controversy.