Its author was not terribly charismatic and had a somewhat counterproductive marketing strategy. In a world in which building alliances and finding sympathetic voices and supporters is critical to messaging, he burnt bridges (or blew them up).

All that for a message which is inherently less palatable. It's often said that news has a negativity bias, but that tends to be small negativities: petty crimes and small or remote disasters, not long-term, distant, and intractable existential crises.

Cassandra was ignored. Cassandra was, however, correct.

(Not all doomsayers are, of course. But judging a message soley on its conclusion, as is quite often the case, is tiself a major failure of reason.)