The gaslighting is so hard precisely because troons of Reddit know that the guy is a sane individual who has witnessed something deeply unhealthy.

This is the part that always gets me. Their language is so precisely worded as to unconsciously reveal they know just how fucking creepy and inappropriate the behavior is, and they pre-empt that very natural and correct feeling with a shitload of "ignore your gut, it's actually totally normal" bullshit. Like how much more obvious can you be? It's like the "I'm not racist, but..." of being a male pervert.