I believe JohnXfce is just a troll. He posted on the 10th and hasn't revisited the issue to back up his rant
There are a lot of half truths, but that's pretty much it. A lot of what John mentioned is also false, like amd catalyst and i915 freezing and crashing when dragging windows. That actually sounds like a poorly configured distribution with mismatched kernel modules or or X / mesa combos.
In that case, I'm not going to read any more of his stuff until he gives us more info rather than spilling orange juice on everyone's shirts.