> Wolf3D didn't have textured floors and ceilings because of performance reasons, but several other similar games had them

Blake Stone Rise of the Triad used later versions of the Wolf3D engine and had textured floors/ceilings

> Doom and IIRC Duke Nukem as well used a BSP engine which was much more flexible

Duke Nukem (Build engine) did not use BSP

https://www.jonof.id.au/forum/topic-137.html#msg1548