Your friend probably doesn't even know that the sushiswap dev dump $8 million tokens. He's trying to pull a Charlie Lee if you know what I mean. Many of the previous supporters have lost confidence because of what he did. You know what happens to projects like that? It drops tremendously.
This is true, and it is a prime example how not to trust everything that gets listed on Binance. Yes, Binance is a great exchange but let's not forget that as an exchange they have their own agenda - getting those fees so any listing that'll bring them that will do!
Sushiswap is probably not the best investment so looking at other exchanges (if that's your thing) wouldn't hurt.