So is the fundamental problem with blockchain, as described here anyway, that you can basically do all of the cool parts of blockchain that people get excited a

So is the fundamental problem with blockchain, as described here anyway, that you can basically do all of the cool parts of blockchain that people get excited about, but using a central service instead? I feel like I don't really understand that, because wouldn't that mean you'd have to re-solve a lot of problems on your own, with your own team? Wouldn't it be easier to figure out how to plug blockchain into this central service instead?