International cooperation can be achieved without an integrated political and economic structure. My country doesn't need to have the same economic policies and regulations as your country to live in harmony with you, or to take on international projects together like sending aid to some natural disaster, or doctors to communities that need them, or to agree in standards, or to foster academic research.
"a more integrated global political and economic structure" means 1. bodies that have political power over national governments, which would make the implementation of standard regulations easier and 2. open borders for trade. Of course a billionaire involved in a number of translational companies wants this.
As far as consolidating power goes, the US and China have some pretty big fish because their economies have been on steroids for a while. But other countries rely on national regulation to keep their national companies and local economies from being overrun by these big players. Least you know monopolies wouldn't exist only on the national level, but internationally, and then what do you do? National monopolies are a pain to get rid of, those would only be worse.