There was speculation that "something is not right" when observers have spotted someone was repeatedly buying little-known crypto assets like NFTs before being featured on OpenSea's website, then dump the assets once it generates enough hype for a nice profit (link). Once or twice wouldn't have aroused suspicion, but this was probably done multiple times, enough that these transactions were investigated and eventually linked to Nathaniel Chastain, a former product manager at OpenSea.
But while such practices are unfair and indeed being frowned upon, the apparent lack of vigilance of OpenSea management staff may also be partly to blame. If the allegations are true, how did Chastain knew what NFTs would be shortly up for grabs? They seem to have no safety checks regarding the secrecy of what NFT items are to be featured on their website, and if they do have something like that, they failed to screen the right people to uphold such secrecy.
The discovery of Chastain's alleged scheme and his subsequent arrest may serve as a highlight for a few crypto experts to push their case for more crypto regulations. For while crypto can serve its purpose as the future of digital currencies, there are still plenty of persons who will try and abuse the system to gain personal profit, at the expense of weakening the reputation of crypto as a whole.
More details of the news are in the link below.
source: https://www.theguardian.com/technology/2021/sep/16/nft-trader-opensea-bans-insider-trading-after-employee-rakes-in-profit