All modern espers are descended, in some way or another, from these Ancients. The Ancients, however, were far more powerful than any modern psychic talent ? with the possible exception of Sonnet. And their group consciousness is just that: all the minds and all the esper powers of every Ancient who ever lived. If the Akai Kiba really wanted to, it could probably throw the Earth out of its orbit.
It can easily be seen that any organization wishing to take over the world would love to get its hands on power like this, even if it were never to be used.
However, the only way to touch these powers is to be, in part, in the group mind. And the only way to be in the group mind is to be an Ancient. Hence the creation of Lan.
Talon, however, has no clue what they'd be getting into if they could touch that power. While one person talking is speech, a lot of people talking ? even if they're all saying the same thing ? becomes a Confused Noise. The Akai Kiba does not reason. It does not differentiate to much of a useful degree. It can be summoned when in the grip of a strong emotion, but the only thing it will be then "thinking" of is that emotion: Lan unconsciously summons it in rage, and the woman-shape it takes is incapable of anything but that blind rage and will to destroy.
Moreover, the temptation of being part of it is hard to resist; probably harder now than in the days when the Espers walked the earth, because now it is the only place where people like the one joining it may be found. The only place where there are those who understand what it is to be an Esper.