My take without going into specifics is that it's hard to assess how "objective" things are, but it's way better to have some metrics than none. Metrics give you a clear baseline and from there you can start a discussion around other aspects. Amir uses the Klippel method, which is a proven method to isolate box speaker response as precisely as possible. What is proven in this context? That it was developed over a long time by expert practitioners in the subject, using their best judgement and a method that has repeatable science in it.
So summing up: Are the measurements perfect in objective terms? Probably not, but way better than pure opinion based arguments IMO (to be redundant).
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