Couldn’t we exist as angels do in spiritual realms?
No, for angels are aware that they don’t really exist, for their reality is so Godly that its like a fish in the water – whereas a dog might not think that he is dependent on oxygen, the fish knows he is dependent on the water, which is why they don’t jump out of it, whereas dogs do swim.
In other words, for us to be us, we need to be born in a world where our source – like in the matrix – is hidden.
Precisely, by not seeing our source code, not realizing that all of our life is truly dependent, no different from the fish in the water, on God, (for both our soul is Divinity and our bodies of course like all matter are constantly refreshed from the creators source code, like the harddrive presenting the Ram that the computer shows you) hence we exist.
Now that we exist, we have freedom of choice.
Remember, God himself created the darkness, but not so we should be blind, rather that we should use our soul and our minds eye, to reveal the light.