You could effectively call ToAU something seperate to FFXI's main story. You're on a different continent with different way of life and politics unrelated to anything related to Vana'diel. ToAU, in fact, has A LOT to offer if SE actually decides to expand some much needed focus there. There's absolutely no reason to up and delete ToAU content.
Mythic weapons are not hard to make. They are, however, very time consuming. Some are far from being "generic" weapons. See Nirvana, Terpsichore.
And speak for yourself. I, as well as others in my LS and others on my server still do einherjar, salvage, assault, and nyzul isle. It really comes down to actually finding some like minded people to do these things with you.
Adjustments are coming to ToAU endgame, but instead of suggesting scrapping ToAU, there needs to be new reasons to venture back there, even if it's for a mini add on.