I have at least 50 pleco caves, but I breed a number of plecos. Having movable caves is a big help for a number of reasons. I work with groups of plecos not pairs or reverse trios. It is important for a dad to be able to defend a cave with eggs or wigglers in it. I need to be able to pull a cave with a dad and babies at times as well. I still have a few 100 plecos across 11 dedicated pleco breeding and grow tanks. A pile of stuff wont work for me.
I also use an assortment of shapes and sizes in caves since plecos tend to grow and thus need to upgrade to a larger cave. I also find different species have different preferences for the shape and/or material of a cave.
The PC forum is not dead, it is just slower than it used to be. But, unlike on social media, the information does not die on PC and it is a lot more accurate.