But that very same reference states that all spiritual beings have reiryoku and reiatsu. But i do get your point. However you proved mine. All beings have reiryoku. It is their inherent power. I referenced the article you posted. Reiryoku is the amount of energy a being has. not how it is used. Zaraki's durability and reiryoku are as high as they are because he has some much power. He isn't making his skin harder deliberately. It's his inherent strength. Reiryoku could be compared to chakra or bioelectricity. They are all forms of energy. Using said energy as physical power does not make it an energy based attack any more than us using the energy in our bodies to type what we are writing.
Low back in the day i was known as the worst bleach fanboy. I know what I'm saying. Been with it for around 8 years. and it was the first thing i edited (Bleach). I know that reiryoku and reiatsu are related. Everything pertaining to spiritual power in bleach is. What you're missing in my point is that it is merely the basis of shinigami power, whether it be strength, durability, stamina or anything. It is a form of energy like all forms of strength. They are derived from an energy of some type. In bleach it is reiatsu. Reiatsu is merely reishi, the same thing shinigami themselves are composed of. They are not physical beings to begin with. Reishi are the building blocks of spiritual things in bleach. That is why when quincy absorb power, they do not absorb reiryoku, or reiatsu, they absorb reishi which encompasses both. The equivalent of atoms in bleach. I do know what I'm saying.