It is not a good idea, as nobody knows when the market turns into bearish or bullish. Bear market can last for years
and that would mean not having ICOs for years according to your proposal. We have to adopt to the market conditions,
as all the participants are affected with bear market.
They will start an ICO as anytime they wish.
The market status is uncertain but their job during the ICO is just to raise funds, if there are still investors who will invest, then
that means investors are willing to wait for a longer period for their return.