How many people these days bi-amp? I am guessing nearly no one.
Bi-wiring, where you separate out the speaker cables into upper and lower frequencies is done all the time. But, bi-amping, where we use one power amplifier for the treble and another for the woofer is looking increasingly as a thing of the past. And, for good reason.
Today's power amplifiers are great at all ends of the frequency spectrum, something definitely not true a few decades ago. Back then, some amps had a great and powerful bottom end but a rather objectionable top end, or the opposite. Rarely did you have both in one box.
Today, that's rarely even a thought. One of our BHK or Stellar amps all have wonderful slam and extension on the bottom end, with a sweet and open top end.
It does my heart good to see one of our cherished traditions from long ago disappear into the mists of time because we've eliminated the need for it.
Can't think of a better reason to not have something than to not need it anymore.