Looking at those figures, it would make more sense for redhat to buy ibm.
Either you are missing sarcasm tags or you and I must be reading different numbers.
IBM $79b revenue vs RedHad $2.9b revenue, 3.6% the revenue of IBM.
IBM profits $5.8b (would have been $12.9b if they didn't have a one-off write-down) vs RedHat $259m, 4.4% of IBM's profits.
So IBM has 29 times more revenue and 22 times greater profits, and you think RedHat should have bought IBM?