The messiness is a signal to watch for. No, Not all messiness has deep meaning or sign of a issue. Some people just don't like to vacuum. I haven't ever ironed a garment of my own, but I do care about my appearance.
However messiness turned into hoarding definitely is a huge mental issue. I believe the reason that not cleaning is asked on functionality tests is to look for hoarding and other with managing their environment issues, some with OCD, etc.
While this question might not mean anything in your life, there are others that it could be very beneficial.