Ronald 7
Because the Same Matter is joining the Accretion Disc
We basically are looking straight down its throat
?
Why should matter cover it just because matter "swirls in 3d"?
Why can you see ANY shadow?
In this case, the "shadow" is the same SORT of shadow as the shadow of the Moon (i.e. the part of the "face" of the Moon that is not bright, that is not reflecting sunlight)
More info regarding **what that picture actually is**:
https://astronomy.com/news/2019/04/the-nature-of-m87-a-look-at-a-supermassive-black-hole
neb
We can see near the event horizon because it is a rotating black hole so the matter surrounding it is not spherically symmetric, but symmetric about the axis of rotation. I would guess that axis of rotation has a small angle with earth.
As an afterthought, depending on angles, you can also see the accretion disk from the backside of the blackhole as the light is curved around from the backside of the black hole to appear to be above/below/side.