Personally, I think they are just overreacting to their excessive optimism about the prevalence of life in our solar system before any of the probe missions to Mars and Venus. If you read old astronomy books from that period they were full of speculation and hope that we would easily establish contact with other forms of life. They were burnt badly by the discovery that all other planets and moons in our solar system are much harsher environments than we initially expected and they received a lashing from the media after headlines full of starry eyed promises. It seems to be a similar effect to an AI winter where initial progress and optimism is met with challenges and limitations that turn fickle public opinion against the science, the researchers then internalize these beliefs or they become fringe pariahs. Thankfully some brave souls persevere and eventually prove the field isn't worthless after all.