Right. Try going to Uniswap or Sushiswap or if you like Bittrex, and try go into their socalled private rounds, 90% discounts or whatever. Buy the coin and tell me when it goes listing how much the price dumps, if you can. I've seen too many public price listings way lower than private sale rounds:)
Of course, there are cases when a coin is sold on DEX for less than at an early stage of sale. And I can give such an example of an unsuccessful investment in a PolyPad coin, the current price of which is 4 times lower than a private round. But, for example, a project like Cirus showed a profit of X16 from the private sale price and, accordingly, covered the losses of PolyPad and, if necessary, could cover another 15 unsuccessful investments.