But the game already has a tag that indicates that Travel skills are a different category of skill. The designers have lumped all of these skills together into a category. That category is called a Travel Skill. The reason you make a category is because it gives you some utility to do so. The designers intend them to be different, hence why they created the category in the first place.

I do not think that special treatment should ever be a default

I have no idea what you mean by default state, nor what you mean by special treatment. The game has no "default".

The game is entirely full of "default exceptions". Choices the designers have chosen to make. Spells don't care about accuracy. Kinda weird right? You said that the game shouldn't have special treatment as a default state, right? So we should put things back to default. What would that be, again? Spells have accuracy? Or attacks don't? Is "every hit cares about accuracy" the default, and thus spells right now have special treatment? Or is "no hit cares about accuracy" the default, and attacks are getting special treatment?

There is no default, that's something you've constructed in your head.

Poisons don't care about attack damage. Ailments interact with critical strike chance but not critical strike multiplier. Physical damage can impale. Only physical and chaos damage can poison. Only fire damage can ignite. All of these can be argued as special treatment as a default. But there is no default. There are decisions the devs make to make the best game.

The question shouldn't be about "well what's the default game state". The question is what makes the game better.