I have observed for the last five months, tokens which was listed on the exchange usually dropped in terms of price and until now have not yet recover to it's ICO price. With this scenario i think with it is better to buy tokens on the exchange, most probably on dex.
Apparently, you are absolutely right, because such a trend persisted for quite a long time. But this is all due to negative phenomena on the market, including due to the low price of Bitcoin, since it is Bitcoin that influences pricing of all crypto currency.