I think that's too few, at least there must be more than 80% of coins that will die, because only a few will survive.
and most new projects will just make the same mistakes, as the ones already done.
create a new project promoting, then the fomo ends and the project dies.
Most of the project dies due to less demand of holders but some of them dies because they are created scam which will just collect money from users and will not provide any profit to its holders. From the year of origination of crypto there are large number of coins that did not give any profit to its costumers and died after passing through a single bear season.
Some projects are also successful because of their trend in market so when it ends such coin become disappear with little value. But still we have to take this risk because if we are not ready to take risk then our achievement will be doubtful but be careful and do a thorough research first.