The trouble with being right when most others are wrong comes with the compensation mechanisms needed to stay cheery throught the shunning and taunting that comes with being easily singled out. In the goldbug case, morale is kept up with the realization that fiat currencies eventually go to zero value: the hyperinflation narrative. This kind of anchoring makes it tempting to keep doubling down when proven right again and again. You can think of it as inverse boosterism.
Eventually, though, the tide shifts and excitement turns into embarrassment. The fellow who was right when most others were wrong turns into yet another shark-jumper, like the people pushing real estate in '06 and Internet geeks in '99. Unlike the normal booster, the prescient doomsayer isn't forgiven - especially if his/her brand of doomsaying doesn't flack (or shill) for the government.
Predicting a new Ice Age is a way to get attention, 'tis true, but I'm beginning to wonder if Mr. Corbyn is approaching the shark-jumping moment. Sad to say, the prophetic minority is all-but-fated to go over the top. The psychological burden of bucking pap spread widely, and the consequent need to keep heart, get them in the end.
Piers is not always right. He is human after all. This summer he did make an error IMHO when he claimed the excessive heat in Russia was due to the active sun. The sun never really got into the active warming stage. Neutral or average activity for a short period this summer. Solar activity is currently more then 50 % below average. The excessive heat this summer was best explained by the 6 month atmospheric delay between El Nino and atmospheric warming. After all, El Nino is the number one single event generator of green house gases on the planet, simply due to the increase in oceanic water evaporation. El Nino is long gone. Now we are experiencing the cooling affects from the Super La Nina which has been occurring since early this summer. Apparently Piers caught on to all that eventually.