No its not
The scabbards and oden broke shis scales and caused him to bleed.
When luffy used the penetration on the tree in 955 the front part of the trunk remained intact.
I'm saying "breaking his scales" is the same thing as "bypassing durability"
Let's use quantifiable stats. Let's say Kaido can withstand a NUCLEAR BOMB. His scales are literally tough enough to tank Dozens of megatones of TNTS of force including the radiation and debris caused from the explosion.
This is a what if example. I'm not saying it's a fact.
Then the scabbards manage to do more damage than said nuclear bomb to kaido using Ryou. You are not going to seriously say the scabbards literally have MORE POWER THAN A NUCLEAR BOMB. Right?
That's what I mean when I say this is a video game. In a video game, like let's say Injustice. I can BLOCK certain devasting attacks just by having the CORRECT TYPE OF GUARD. In that moment, my durability is essentially INFINITY. No attack of a certain type can break my guard no matter the force.
But then Guard break attacks exist. There exists a TYPE OF ATTACK that immediately breaks my type of guard Even though the guard break attack is weaker than the other attacks that failed to break said guard.
That's theechanic Oda is using to explain Ryou. Whether he knows it or not. He's doing video game logic.
"Bypassing durability" is basically making kaido work the same way normal people do. Look at it this way:
Normal punches on a human body aren't inherently damaging to the skin right? If you get punched in the stomach, the damage on your skin isn't really the issue. it's the shock wave travelling into you stomach and messing up your organs that's the issue
Kaido for whatever reason prevents that shockwave of force from entering him normally and that's where Ryou comes in. It forces the shock wave passed kaido's durability.
And same applies to swords. A sword on a normal person cuts through skin and into organs.
Kaido prevents swords from even getting passed his skin but Ryou essentially bypasses whatever it is that makes Kaido tough and cuts through his skin and organs.
Ryou isn't breaking Kaido's durability. Both for luffy and Oden. It's IGNORING THEM. Like how guard break attacks in video games ignore the guard it's self. The attacks aren't Stronger than regular attacks. They are just specifically the correct attacks to ignore the durability of the person guarding.
And yes I know, this contradicts certain other concepts such as Zoro cutting steel but it's what Oda is doing. Oda doesn't know he's doing it but it is what it is