There's a spectrum of issues with older content. Poor ilvl synch, potency adjustments over the years, fight mechanic changes that have occurred as a result of nerfs or the trust system, how quickly you outlevel the content itself, etc. just all culminate in trivializing the old content.

Sure, go back and adjust ilvl synch in older content but that isn't going to instantly solve the problem either and will just as likely create new problems too. As much as I would like to actually do mechanics again for older content, can you imagine how much of an uproar there would be if people were getting stonewalled by Syrcus Tower because I'm sure the larger part of the community doesn't even know them, much less how to resolve them? Instead of dealing with it, people would just leave if it pops up in roulette; look at Orbonne Monastery, people still leave that instance immediately because they don't want to deal with the hassle, even after years of powercreep have rendered most of it trivial (I'm sure Cid has a few more wipes in him).

I want to see it happen. I would love if the community would actually improve as they leveled up after having to deal with some of the more difficult stuff that was once present in the game instead of having level 100 Tanks that don't mitigate, DPS that freestyle their rotation and Curebot Healers but I know this community has become far to coddled by ease that they're more likely to complain about the changes rather than get good.