I recall that one time when SE tried to increase the difficulty on a normal instance. Steps of Faith, anyone? When it first came out players were eating dirt left, right and center. And then came the torrent of complaints and, well, guess what - it got nerfed. Who here thinks they should have left Steps of Faith as it was as a gate for casual level 50?
And then you have the guy in the other thread talking about Coil of Bahamut? Well what do you know - guess you can't just faceroll/1-2-3 through content after all. So what's with all the comments about underperforming players who don't know their skills succeeding at the game? You mean, allowing them to complete normal content?
And when Titan EX first came out - I doubt that those uninterested, not invested, unmotivated players would have been able to clear that trial.
Or the Demon Wall way back when it was new content. Contrary to what others might claim, I remain unconvinced that lazy players are able to clear difficult content, in any period.