The original builder of the house had applied random bits of wood at the front edges of the steps where the treads and risers meet. I’m guessing the purpose of this was to give the effect of a bullnose edge under the carpeting.
At the right side of the stairs, you can see there is drywall peeking out between the railing skirt board and the steps. So, if the weird piece-meal steps were not enough, this rough drywall sandwich was certainly very daunting.