I don't think big businesses have ever avoided politics. Try being openly gay and get hired in the 80s or being a woman trying to be an executive in the 80s. Businesses did openly discriminate. And that is political.
The shift happened because businesses became dependent on more and more talent for continued growth. Suddenly having a large contingent of your workforce threaten to quit because some dude wants to spout off about women not being as naturally smart as men is really bad business; and it's not surprising that businesses respond to the incentives and axe the dude spouting off.