How so?

1) The commercialism of it has greatly undercut its potential. All the information in the world could be available for free, but it's not; recall google books. The profit motive and the need to sell ads (and thus, people's data) is also a major reason that e.g. Facebook sucks and is socially harmful.
2) What was meant to be decentralized is now largely in the hands of a few powerful corporations. There are basically 5 websites now.
3) We have unprecedented access to information. You can look up any empirical fact on your phone in a couple seconds. This has somehow lead to pretty much everyone believing in insane conspiracy theories, alternative health woo, political extremism, etc.

Ahahahahahahhahahahahahahahahahahahhahahahahaha

Why are you laughing? He's not wrong.