You should look more closely at the numbers.
Yes, forkdelta allows anyone to sell their ERC20 tokens, but how much trading volume is actually going on?
You will find that mostly, there is ZERO trading going on.

forkdelta is not the problem.
decentralized exchanges like idex and forkdelta are necessary in the crypto world and help its economy.
Bounty hunters dumping is a thing of the past.
In order for the price of a token to truly crash, there would need to be a simultaneous dump on a high volume exchange.
Otherwise the 1 to 3% typically alloted to bounty hunters won't make any difference.

Now that most ICOs fail, there isn't even a place to make that kind of a dump anymore.