He was probably exaggerating. However he is correct when he says that anyone who dares post that the price might go down for whatever reason is probably going to get flamed by many members of this forum. Theres some sort of unspoken rule about never predicting that bitcoin might go lower, even temporarily...
Exaggeration is the key word. He doesn't just predict a dip, he calls for a big crash and then rejoices and celebrates every minor dip as if it were a newly discovered cure for cancer or an end to poverty. Every small setback to Bitcoin is treated as a wonderful positive thing. It's as if he hates Bitcoin. No wonder he's almost universally considered to be a troll.
Even many so-called "permabulls" routinely predict temporary price decreases when they are called for. It's a matter of degree.