According to the Dictionary on Google
scal·a·bil·i·ty
/ˌskāləˈbilədē/
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noun
noun: scalability; noun: scaleability
the capacity to be changed in size or scale.
"scalability of the service has not been an issue"
the ability of a computing process to be used or produced in a range of capabilities.
"the key is the scalability of the software"
Even says change in size, ie: Blocksize
Which makes you wonder why delusional people claim block size has nothing to do with scaling.

You're just trying to confuse people by appealing to authority and making this about semantics. If we're playing that game, I can just as easily point to Wikipedia's definition:
But this isn't about proving which definition is correct. That doesn't matter. The issue is the distinction between
throughput and
the system's ability to handle throughput -- and how we can improve the latter. I'm not interested in adding throughput without regard for the costs.