In my experience, buying at the peak can really make you go lose specially when the bubble pops as the price will drastically go down but I think its not right to call them idiots since some of them might be a newbie or noobs in the cryptocurrency market.

They might have no choice but to buy the peak but imo thats not a good move at all specially for long term holdings , maybe on shorting it, it will work but not with longing it. Bitcoin price is pretty volatile as you can see so shorting/ swing trades for it will work.