But we have been in [light] descensions more recently [than 500 billion years]. So how is this different?
It's not the same. The cosmos ambience will feel less electrical, in the same way one's dreamtime feels less like a fiery electrical experience than when one is awake. Sleeping is more of a soul-based feminine experience than being awake.
The descent / ascent of masculine / feminine examines these two poles separately by studying each in its isolated dominance. As separate poles they express within species as male and female. The feminine-infused activity found in the dreamtime is an integrated experience in which feminine qualities permeate and blend with masculine activity.
For instance, in the awake time, light comes from an external source. In the dreamtime, objects and the Earth are lit from within. Light is integrated with matter; not derived from an external source. This ability to emanate light, is the nature of the etheric realms. It is the reason why beings who visit from the soul (etheric) world are often mistaken for angels. They glow.