Carmack has simply hit a ceiling that others won't let him pass. Carmack isn't in authority, and as such, he has to rely purely on influence. Hard to do when you are focused on technology, because technology and humans are quite different (yet also similar). He's making it clear that his political effectiveness is limited and he has no motivation to continue his fight. It happens. You only have so much energy to spend in any given time period, you have to spend it where it will do you and others the most good. Everyone eventually learns from these things. It takes time. And how each person defines success will be a bit different.