It really depends on the project, there are some extremely popular ICO's even during 2018, shilled by so called "whales" and some social media personalities with huge networks
of influence. In fact, the term whale perhaps only applies correctly to ICO investments. What happens for these projects is that usually ICO reaches hardcap within a couple of
days, if not hours of the announcement. If the hardcap is also on the lower end like 10 million USD, the exchange price might never come back to the ICO levels, and just take
off. In other less popular projects with more risky teams, etc. you can usually get it cheaper on the exchange during these bearish markets.
There are 2 major options when you think of investin in an ICO.
1-You aim for great profits like 5x or 10x and then you need to buy during ICO so that you won't miss it.
2-You be conservative and you think the token price will be even lower when it gets listed on an exchange. Then you can buy it through the exchange.