Not that the deaths on 9/11 weren't tragic but 9/11 is certainly not important compared to what is happening in the world now.
It wasn't weighty then, either. Not when 8 times as many Americans died the same year from common killing, and a few hundred thousand more from air pollution. Not when 150k folk died that day of any cause. And all the other killings - Bagdad, Paris, Ankara - barely stack up at all to any irregularity in the 170k that die each day.
But you know what gains from their popularisation? Weapon sellers and governments that like to go to war. But oddly, they don't like to popularise happenings like the deadlier Bhopal disaster of 1983 (~4 000 killed), or the Great Smog of 1952 (~12 000 killed). More folk get killed by lightning strikes in America than by dread, I bet. All modern disasters, but not so easily gained from, but if it's a modern disaster that can be wielded to provoke upholding for war, it's done. Disgusting.
The only weight the September 11 attacks have is being the bloodiest fear attack in all the past.