That part I disagree with.
Apps that are using unshaded or regular lighting and have configured colors specifically will all look broken and washed out. Being able to toggle that check box off to check is a huge advantage to tracking down what the real issue is instead of just assuming 3.4 is broken.
As I recall, even the JME color constants look messed up with gamma=true because there is no easy programmatic way of using setAsSrgb() in a way that is different when gamma is/isn’t enabled.