No, i do not agree with you there are success projects this year, also there are many fails projects, although fail projects more than success project but still exist.
Successful projects in 2019 do not tell too many problems. in 2020 or 2021 it may die or be replaced by other altcoins. And I agree with the thinking, there is no really good project in the long term. Except for bitcoin
This year was not successful for the ICOs, IEOs also didn't leave a nice return due to the market conditions. Other altcoins can replace the current ones but I doubt the top altcoins will be under questions during the next 3 years. Investors lost confidence after the recent market crash, the lack of development in the projects and more. Altcoins need to see an uptrend if ETH price crosses the $300 for the next quarter. After the bull market, the investors will rush the altcoin exchanges for buying more altcoins. The Kucoin exchange has such coins with small market cap and low daily turnover. In case of the bull run, these IEO altcoins will gain a huge advantage like the current top altcoins which have low performance in the time of the bear markets.