I think what it really means is:? What does this even mean? The literal size of the speaker?
If you accept the premise that speaker manufacturers measure/setup/tune their speakers in an anechoic or quasi-anechoic method,
then they are no doubt doing so in the far-field, (where measurements need to be as per a couple of links in my last post.)
So this is where all the driver(s) EQ's, xover design, directivity matching, etc, took place..
And is where the speaker is designed to work best.
That minimum distance mic-to-speaker, that gets into the far-field, can most often be approximated by 3X the largest speaker dimension.
The minimum far-field distance is where all frequencies begin to attenuate at -6dB per doubling of distance, and continue to do so with greater distance.
So any listening distance further than the 3X r.o.t is hearing the speaker as it was designed, and as it measures..
(1m response curve specs are simply mathematical adjustments to measurements made in the far-field, unless the speaker is truly small enough to measure accurately at 1m)
I know how often folks talk about trying to recreate what the artist intended....
how about what the speaker manufacture intended ? Lol
Because any listening distance closer than the onset of far-field can't be such !