There are many fish that shouldn’t be sold in numbers, period. Many staples of the hobby aren’t the most well-suited to the average tank. How many tanks can house a Naso or Unicorn Tang once they get near full size? Or even house a Blue Tang (Dory) properly? I cannot help but cringe when I see even a Sailfin in a tank that clearly doesn’t take into consideration the size at which they can reach.
Many Acanthurus Tangs simply aren’t well-suited to captivity, they get too large, too active, and are behaviorally problematic. Corallivore butterflies, Moorish Idols, Grunts and Sweetlips, and many examples are all too commonly sold as suitable aquarium fish for the average consumer.
A 24” fish is huge. The longest tank I have heard of is 120” or 3 meters, in a 10’ tank the fish can only swim five body lengths, and the fish in question in the OP’s thread is anything but a sedentary one.
Best left in the ocean or public aquariums, which may or may not do a better job than the average dedicated aquarist.
I sometimes come across an exotic fish or two and I’m like “wow I wish I had that”, but 9/10 times when I do research on it I find out reasons why it’s not commonly kept if at all.