Vertical integration may have its problems, but it does give firms a chance to control suppliers more easily. That may fix some of the quality and social sustainability issues firms who outsource a lot are frequently combating.
Are we seeing a trend back toward vertical integration?
And will Wall Street let firms do it? One problem is that it increases the assets of a firm, so the return on assets ratio gets harder to improve.
http://supplychainmit.com/2016/03/10/new-supplier-strategies-revive-important-corporate-questions/