Yes and no. Getting to the point of "some people can't do" is a bit too much for these days, but there has to be a difference somewhere.
What I find to be the best compromise is for "tiers".
As the level cap/ilevel raise, new content tiers are released. Once the new one is out (efficiently doable only by organized groups and people with some dedication to the game, not necessarily only freaks who play 24/7 of course) the old one becomes easier thanks to: 1) temporary zone buffs, 2) new gear
That way everybody gets to try content, but casual player will complete it later.
This is how it works in most other MMOs, FFXIV included. It would need to be adapted in several ways to work in FFXI, but it's something they could and should definitely do.
It sounds "elitist", but there has to be a difference somewhere, for the sake of EVERYBODY, not just the elitist.
It gives hardcore player something to work for to sedate their thirst for glory and power.
It gives other players something to look forward to, as far as it may seems, a far goal that will give them a sense of progression.
If everybody looks the same, plays the same, does the same... it all becomes boring and you slowly stop being interested in the game in a small time, eventually dropping it.