I agree with you. I'm often surprised when I get to the measurements part of a Stereophile speaker review, and read about strange anomalies of the design, and then see a not-so-good waterfall plot from a very expensive speaker.
Flat frequency response
I am often surprised by the number of speakers with "gee-whiz bang" technology but can't even get speaker design 101 right. I can see the benefit of avoiding a lot of signal processing but preferences notwithstanding, flat frequency response seems like the logical place to start and then progress from there.
1) Why is it so hard to achieve?
2) Does it matter?
3) Is it reasonable to say when you skip the basics you are only progressing on a flawed foundation.