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.
As with the help of Ethereum blockchain where it was super easy to generate any coin it was easy to launch any ico with high promising goals and convince people to make their money multiple x.
Those scam or ordinary platform make alt market dirty game. And this impact very badly on the genion project where many traders lost their interest.
It happened then and still happening now where most projects are nothing but worthless, they come up with absurd ideas just to make way with funds generated and most of these projects are having their IEOs on most exchanges known for having bad records. On the part of Ethereum blockchain, I see it as a blockchain contributing its own obligation to the development of the crypto space, so whatever anyone makes of it doesn't concern the blockchain. Just like many scam projects used Ethereum blockchain in the same way many good projects used Ethereum blockchain and are still using it; therefore it is all a matter of perspective.
Basically often developers of new altcoins do not have clear ideas and objectives to achieve and they are not sure what their project is going to provide to users.
As you mentioned, they are simply able to launch projects but lack the capability of rubbing the project through ups and downs.
They just simply create a new project and launch it in the market without a proper layout of where the project will go in the long run. They just create a new altcoin for the sake of money (simply making a new project as their source of money) and will just abandon after they collect enough money for their own good. They just repeat this cycle over and over that's why more altcoins keep on dying.