>Lack of regulation is guaranteed to benefit already-big, though.

Not neccessarly, it depends on how educated market participants are. Shouldn't a world that becomes more and more informed, connected and educated not become less regulated?

>Unchecked corporations become oligopolies or monopolies.

But not forever, less regulation also means more opportunity for competitors. And educated customers would be aware of the situation and just ignore the monopolies if they can buy somewhere else.