O yes for example practically all small signal electronics have moved into the realm of transparent, so there the struggle is done and gone.
there is no trying to squeeze a balloon and have it pop out somewhere however you try ? Like when you had to trade some undesirable factor for another different undesirable factor and make your thing different rather than better
Speakers was designed decades before thiel and small developed a working theory on how loudspeaker drivers even work and the math behind different bass alignments ? It’s must have been the wild west with flogiston and eather all around you
even the most rational designers must have struggled to grasp what was really going on and made some crude model of reality for themselves to get something done . And then acoustics and directivity on top of that .
So even if they did measures transducers back then they did not had the full picture , so that quote was probably right for its time.
You probably had to judge which of your crude measurements actually meant something