You should know the answer yourself: the difference is that usability is a
core quality of any project.
I as a maintainer can be neutral towards a number of features and patch
attributes that i dont consider key aspects. (although they can grow out to
become key features in the future. SMP was a fringe thing 15 years ago.)
Usability is not an attribute you can ignore and i for sure am never neutral
towards usability deficiencies in patches - i consider usability a key
quality.
Whether a feature is usable or not is sure a metric of 'goodness'.
You have restricted your metric of goodness artificially to not include
usability. You do that by claiming that the user-space tooling of KVM, while
being functionally absolutely essential for any user to even try out KVM, is
'separate' and has no quality connection with the kernel bits of KVM.
It is a convenient argument that allows you to do the kernel bits only. It is
absolutely catastrophic to the user who'd like to see a usable solution and a
single project who stands behind their tech.
Thus, _today_, after years of neglect, you can claim that none of the dozens
of usability problems of KVM has anything to do with the features you are
working on today. It's in a separate project (the so-called 'Qemu' package)
after all - none of KVM's business.
In reality if you consider it a single project then those bugs were all
usability problems introduced earlier on, years ago, when a piece of
functionality was exposed via KVM. It adds up and now you claim they have
nothing to do with current work.
This is why i consider that line of argument rather dishonest ...
Ingo
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