First it might be confusing to taggers and new users who are just setting up their blacklist for the first time.

Second is it even needed to have 2 tags that mean the same thing since soiled_diaper is already a thing?

I want to fix that, but the implication chain is a bit confusing to navigate, with things that should be aliased are instead implicated, words that have different meanings but are in reality used to represent the same thing, mainly scat and feces, see topic #31198

Looking at the implication chain ...

-> soiled diaper -> messy diaper -> soiling -> feces

This seems to be the main chain, with lots of redundant implications, like soiling diaper implying diaper and soiling when messy diaper already does that, though i think soiled should be aliased to messy, see topic #33263 though "soiled" can mean wet, but... there is also messing diaper which has no alias or implications...

In general, these tags need LOTS of cleanup. But the transitives they have makes it a bit difficult to BUR it away easily.

Edit: Do'h I'm a dumb ass, seriously misread the title lmao. Point still stands though.

I naively assumed that mess/messy are generic but this doesn't sound like they are? Guess I'll go read the definitions...

"Messy" isn't directly related to messy diapers, as it simply means something being dirty or unkempt. It doesn't have to involve diapers or bodily waste/fluids at all, or even a person (a room with a bunch of things lying around on the floor is messy, an unorganized desk is messy).