Room acoustics and speaker placement make a huge difference in frequency response and listening enjoyment.
Continuing to harp on "accuracy" and "objectivity" while simultaneously admitting that enjoyment is subjective and that some listeners prefer clinically "less accurate" signatures doesn't make sense to me.
Fundamentally, I just don't believe you can measure and quantify everything about the listening experience.
Many speakers that are widely regarded as excellent have truly crappy looking graphs.