Read the help text..
Yes, we care about features that MATTER. But if compiles start using
features that don't really matter, and make a specific kernel _too_
specific, then we need to reign in the madness.
IOW, it's a balance. On one hand, yes, the uarch makes sense. On the
other, it's just stupid to have to worry about details that don't
realistically make any difference at all - except whether the machine
works or not.
And yes, we could just put this up as a Virtual PC bug. It clearly is. But
in the end, it _still_ all boils down to a balance between "do we actually
win anything by using NOPL statically" vs "do we lose anything by being
too damn inconvenient".