Wrong question, and I suspect you know that. I never implied they should be at the same hardness.
Lemme help you

The question was why would you have a fixed blade hardened that low, or why would you have a light use folder at 58-59HRC.
Or, why have a chef's knife from S35VN steel at 57HRC... Some of the Wusthofs and Henckels are harder than that.
Like I said, "ease of sharpening" is the same as ease of grinding. And back then, when I still had BG-42 Sebenza and those were in production, I definitely have not seen overwhelming number of complaints from the users about sharpening problems. On BF at least.
And frankly, I am very skeptical, how many of you, with 400$ or 600$ sebenszs are sharpening that "blinged out" knife on the first rock they find in the field.
Based on the photos I have seen here, the most devoted/vocal Seb fans in this thread, have not used their knives for anything harder than envelopes anyway.
Hmm, so you know they save money on it, but for someone to assume they do it to save money is "the most ridiculous thing you have heard on this forum"? As in, money saving is just a side effect