The katana bends and gets like unusable (the soft back only makes it more bendable) while a normal eurobean sword would maybe have a stratch on the edges.
At least i think it was like this when i saw a documentary a while ago where they fixated the swords at a table and swinged with power on the other, with the fixated katana i itnk booth had a defect in on the cutting edge but weh the eurobean smord was fixated the katana had enough room to bend

So yea the soft “whoa it is more flexible and agile” part is the weak point