When an investor waits for product development for several years and as a result the project disappears, this is a disaster.
It depends on the attitude of the investor to investments. An experienced investor is diversifying his investments. Loss of investition to one of the projects is inevitable and is not critical for such an investor.
Also here the size of investment still plays an important role. If it is a small capital, then it is problematic to differentiate it. All that remains is to choose less volatile instruments.
The index of dominate of Bitcoin is more then 50%. It mean then when Bitcoin falls down the other cryptocurrencies and tokens falls down too. So devercification do not always help.