As I’ve been saying for a long time now, the Domain is physically vulnerable to Halo. It can be destroyed because it is made from Precursor neuro physics.
Charrum Hakkar, a Precursor build city, was devastated. This literally means the Domain can suffer the same fate if Chief activates a Halo ring in Halo 6. (Wth does everyone think that’s Cortana’s objective? Sheesh! Destroy the domain, stop Cortana, simple.)
There is also more interesting news. The Primordial survived Halo. Either it is capable of resisting the blast or it was just lucky somehow. This implies that it may be possible that a Precursor may emerge in Halo in the future.
Prrhaks Cortana is being controlled by one when it uploaded all its knowledge and “stores personalities” into her.