We already had seen that bitcoin reached $3k before, and many people said that bitcoin would die soon. But then, we saw the price increase step by step and finally reach the new ATH that we do not expect before. Besides that, we know bitcoin is above $30k, and even the price goes down below $30k, bitcoin price will have a chance to increase, and I am sure that will make a new ATH and the price can break $64k. It is about how people believe in bitcoin and still holds bitcoin, and if they are tired of holding bitcoin, they can sell it right now. But they will regret it later when the bitcoin price starts to increase and break the high price.
It will be basically the same, people keep calling bitcoin dead almost all the time and that is like the norm in the crypto world, there are some people for some reason (different reasons) who keep calling bitcoin dead or dying. These could be any type of person, it could be people who just hate crypto from the first time they heard, people who invested and lost, people who didn't invested and envy, people who invested and made money and just do not want others to make the same, people who work for banks and such, basically there are tons of type of people who would be willing to do this.
Long story short we are talking about something that would be just not valid and would be not something we would be willing to listen as crypto people, I personally do not believe that the same could happen here where bitcoin "dies", it will surely not die.