Not convinced. It’s a different set of stairs and a different carpet. I have had stairs with a carpet more similar to the OP that did not have a riser. See elsewhere in these comments for a photo of these stairs, now bare. In the distant past, they were carpeted.
I think they’re cheap stairs without the bullnose. Makes it way easier to carpet. By the looks of the trim this is not a fancy apartment. The lack of bullnose contributes to the optical illusion.
I have those stairs with that carpet.
💯% this is looking down to a mattress at the bottom of the stairs.
Conclusive evidence:
Looking Down
Looking Up

(Sorry I was too lazy to get the low perspective)
Not convinced. It’s a different set of stairs and a different carpet. I have had stairs with a carpet more similar to the OP that did not have a riser. See elsewhere in these comments for a photo of these stairs, now bare. In the distant past, they were carpeted.
I think they’re cheap stairs without the bullnose. Makes it way easier to carpet. By the looks of the trim this is not a fancy apartment. The lack of bullnose contributes to the optical illusion.