That's not an issue. Any website could pull content from the Hive blockchain and post it there using a browser extension tailored to that website.
See, the problem with this guy is that he does not realize the blockchain is different from the front ends. That's why he wrote stuff like the claim that "typically" blockchain-based social media platforms are just one client and all centralized.
When it comes to how Hive is controlled by whales, then he's right but only about the money. Content-wise, removing anything from the chain would require a hardfork and a supermajority (17/20) of the consensus witnesses agreeing.