Why do we raid the Vault of Glass?

This is a repost from reddit but I thought it was a good read. Poster was asking what Guardians are actually doing in the Vault of Glass. Why do we raid it? This answer (from the Grimoire Card) makes the Vault of Glass raid seem so much more monumental:

"Beneath Venus the Vex have constructed a massive structure that is
acting as a meeting point of past, present and future. Their long-term
goal is to basically unchain themselves from the constraints of a
physical reality and turn themselves into a sort of epistomological
computer virus in the very fabric of reality, incorporating the very
idea of themselves into the fundamental laws of the universe. Because in
this space, reality and time are starting to be altered, Oracles and
Gorgons are basically quantum supercomputers that calculate reality and
utilize a weaponized ontology to determine what is and is not real. This
is why a Gorgon can look at you and kill you, because it simply
unwrites you from existence. Oracles make changes and revisions to
reality, and the Templar/Aetheon processes these calculations into

The relic is the last, dying, desperate act of Kabr, a guardian who
managed to send word that this was happening. He basically killed a
Gorgon himself and hammered its corpse into a vessel for the Light,
turning it into a shield that maintains a small space of stable reality
around it. Throughout the raid, the Vex are constantly trying to
separate you from it, throwing it into the past or future where it can’t
be used against them. All the guns and armor you find in the raid are
the remnants of Kabr’s failed raid and will give further info about
their wielders and the events of the raid itself. "


I need to raid right now.