Series of tokens have been developed and some are still in the ICO. Those that have been completed and listed on exchange are really suffering a big blow in term of loss of value in the exchanges. The new ones are scared of being listed on exchange at the moment because of the market situations at the moment and the effects it could possibly have on their tokens' value.
See to it that ethereum has a bad value up to this moment but if you have patience time will come that ethereum will recover thus erc-20 tokens also will increase . Patience is the key is what I am saying .