Light does not travel straight here. The glowing ring wrapped over and under the shadow is one flat disk, bent around the hole by its gravity.
Plasma orbiting at a third of light speed. The side rushing toward you is beamed brighter and bluer; the side receding fades to red.
At 1.5 Schwarzschild radii light itself can orbit. You are looking at your own past, wrapped around the hole.
Past this line no signal returns. Nothing about it feels like a wall.
All of the outside universe is crushed into a shrinking, blue-shifted window behind you. Every direction ahead is the future — and it ends.
Proper time has run out.