In beginning of 2018 there were a lot of alcoins was launched in market, Most of them was just to scam people with typically referral method by social influencers.
This was also a flaw of Ethereum blockchain where any single person can create his own coin with his desired supply and name by costing very low fee.
I also see that in the current BSC, there are a lot of honeypot tokens and it ends in rugpull.
Currently Ethereum has high network fees, there are some fake tokens there too, at least the increase in network fees keeps developers who want to commit fraud from using the Ethereum network for now.
By the way this is a list of dead coins 2017
https://coingeek.com/dead-coins-list-over-1000-crypto-projects-gone-in-2019/