It seems to me not correct that the price of most ERC20 tokens depends on the price of the ether! What do you think?
Always will return to their respective tokens, because after the token is released, nothing can affect the price except the community. And even developers will not be able to control prices. Indeed the global situation, say Bitcoin or Ethereum will have an effect on a token, but I think all tokens or altcoins will also refer to Bitcoin or Ether trends.