I think that IBM know if they get their hands dirty in Red Hat, they wont have much ROI from their investment.
Arguably a lot of OS progress that we are seeing today, especially in the enterprise, is a direct result of IBM’s decades old investments in tools like Eclipse, which was probably the first enterprise grade open source development software, but more importantly, by promoting OS in the enterprise in the late 90s and early 2000s at a time when MS FUD about Linux was at an all time high.