The method does not have to change, this is already a great improvement from the ICO which was not anymore feasible due to high risk of getting scam.
Maybe we will just wait for the right time that the market will recover and eventually we are going to witness more profitable IEO.
The secret to investing in IEO is only trust projects that are listed in reputable exchange.
IEO has a better chance of being reborn as a way of investing and gaining popularity among investors again because this way of investing is more reliable. Here scammers can't go and steal all your money because the exchange stores it temporarily. You can only get losses from the fact that the price of the token will fall and not rise.