I mean, they'll generate some short term cash, sure, but they just lost their entire customer base. No developer of any size can take on the liability and risk of working with Unity again, even if Unity realizes how badly they screwed this up and reverts this.
The current Unity-CEO is the Ex-CEO of Electronic Arts, under him EA was named "Worst Company in America" two consecutive times in 2012 and 2013 by Consumerist Magazine and he's on record saying that game devs that don't focus on microtransactions are "the biggest fucking idiots".