The accusation is that the whole crypto space is shady. There is no value being created, instead investors are being defrauded. And part of the con game is pretending to have very intelligent people keep making progress building very complicated things. Haskell works great to give that impression, though Rust seems to work just fine these days, too.
I don't think Cardano is running a shady exchange, but Cardano sure is traded in shady exchanges and people are losing money trading Cardano. I don't think that's a controversial statement.
People are losing money trading a lot of things, including but not limited to stocks, commodities and cryptocurrencies such as Cardano. I don't really see the issue with that?
I'm guessing it's the shady exchanges. There are several exchanges that have been around for a few years now, do you take issue with all of them or are you thinking of a specific one?
I don't follow the crypto space, but it seems like we might actually want to know which companies are being accused of being shady.