A downside of centralization of power that we don't think about much: there's one neck to choke.
If you're in a situation with rule of law and a healthy democracy, then it's not that big of a deal, because the head of state won't choke anyone's neck, except on behalf of the machine of government that is the emergent will of the electorate.
But if you were in a situation with a head of state that reveled in wanton retribution over perceived slights and had demonstrated their willingness to do it to the centralized companies, that would be a wildly different thing.
One CEO of an aggregator rolling over and kissing a ring instantly throws a pall over the whole ecosystem of the aggregator.
Aggregator's ecosystems are not open, but closed.