Is there anything one can do with useless ERC20 Tokens? For example, a discontinued project or a bunch of scam developers.
You can't do anything with it and just let them die in your wallet. If the project already discontinued and your coin doesn't have any price.
I have some useless altcoins too and i just try to forget it or i have send some to the default address and burn it.

The only thing that you can to take over the development to create a value for your token again.