Some of my issues are as follows.
Cant install dimmers.
Cant simply add a switch/leg
Cant easily find/replace switches
Must troubleshot TWO systems (HV and LV sides)
Relays here are generally in the attic.
Sometimes control voltage is DC.
I like simple things.
The only one that really jumps out to me is you don't want to be in an Arizona attic in the summertime ... makes sense to me.
Certainly running additional "switch loops" with bell wire seems easier that breaking into a wall to run 14/3 and you can still use a dimmer.
I think this would be easier to trouble shoot than a 3 way or 4 way loop.