Disk? You mean, mass storage?

Hardware detection is definitely bloat on this kind of system, because there isn't much variety to begin with.

PnP was created to let people less ans less RTFM-inclined to install new hardware on an platform that won its market share because of its extensibility.

SOCs and SBCs OTOH are generally used in closed embedded systems that are often not at all designed for evolution. Using auto-detection would be a waste of resources and potentially cause problems.