We are discussing a superintelligence, a term which has a particular common meaning on this site.

If we taboo the word and substitute in its definition, Bugmaster's statement becomes:

"Even controlling a single business would be very difficult for the machine that can far surpass all the intellectual activities of any man however clever."

Since "controlling a single business" is in fact one of these activities, this is false, no inference steps required.

Perhaps bugmaster is assuming the AI would be covertly controlling businesses, but if so he should have specified that. I didn't assume that, and in this scenario the AI could be out in the open so to speak. Regardless, it wouldn't change the conclusion. Humans can covertly control businesses.