The market has realized most of these coins are worth nothing and some promoters have no intention of developing the ecosystem
Most ICO projects after finishing will be listed by the development team on tokens because this is the desire of investors. Most development teams will abandon their Altcoin as soon as no one wants to buy or sell it, which makes many Altcoins unable to liquidate or value zero. I can see that this is very bad and the development team of the ICO project only cares about investors' money and abandons the token they have created.