Wasn't just mere back-turning, sadly; after very publicly disassociating themselves from the Bad Man, Scott and Bethany were merrily discussing the prospect of having Alec's name cut from the credits of the impending physical release of NitW, just to show how Extra Good they are. Keeping in mind that, of the three them all billed as the game's "Designers", Alec was the only one who could so much as write a lick of code. Without him, the two of them would've just been "ideas people", with him they have a game they're credited for Art (Scott) and Writing (Bethany) on. And as soon as he was publicly inconvenient, they kicked him under the bus instead of maybe shutting their fucking mouths for even just the weekend first.
Scott's mad because the optics are bad, and because he can't actually produce shit himself and this is going to make anybody think twice about working with him and Bethany on anything when the prospect of getting double-plus-ungood-ditched For The Cause at the slightest turn is now QED. Because Scott's one of those "ideas people", all he can do is compose walls of text, not recognizing how utterly macabre that is at this point. Yes, the "in crowd" is going to tell him how brave and stunning he is and give him all the claps and Twitter likes, but sane people are going to find other places to be now when he wants to pitch things. He thinks that if he paints Alec poorly enough he'll receive absolution, but it's just going to make potential collaborators even more wary of dealing with this asshole who will recite every minor slight and say you gave him PTSD for not kissing his ass if it's a convenient way out.