I think the reason is simple and it is not so much because of the technology that some shitcoins can represent to have or that so much innovation has, everything lies in the business model they represent, both the creators of shitcoins with the Exchanges have a great business, where they can manipulate and extract profits, especially when the shitcoins do a lot of publicity and gain community, the Market Makers are the ones who really earn the most in these cases.
Some in the end only survive with the Pump and Dump .... thus they give movement to the shitcoins and tend to be over time, even when Bitcoin falls in price.