lulz sure it is
The point was that, it's not like hikki just sat around and said, "ok....I think I'll have AI do Final Distance....and I think Ayu will do this........and they'll all cover songs about ME."
Her involvement probably isn't totally minimal, but it's not like it's all HER release.
You can look at other tribute albums, like the one for hide, or the more recent one for Judy and Mary. They are like celebration albums. Lots of hype around them.