I predict that at some point some of these highly outsourced companies will face competition from a former internal "contracting" company (or sets of them) that

I predict that at some point some of these highly outsourced companies will face competition from a former internal "contracting" company (or sets of them) that have been doing substantial portions of the direct work. If a company has fewer and fewer essential "walls" separating what they do at the core vs a possible competitor the risk goes up. If one categorizes a peripheral competency as something that should have been in-house then the company becomes at risk of getting quickly subsumed by a competition hiring contractors that the prime company originally trained. And it might not show up for a while unless some assumption shifts - in the meantime the short term profits might look pretty good. Another risk might be the collapse or disruption at a contracted company where you have less control.