Most high-quality loudspeakers are 4-Ohms

Like I use mass market drivers.

16ohms or or so can sometimes be better sounding. And a easy load for most all amps. 4 ohms is easy to design for try keeping a 3 way or 4 way loudspeaker 16ohms not a easy design chore. But to be fair 4 ohm designs can sound great as do 8 ohm or 16 ohm. Just depends on total design and system said loudspeaker will be used in. In loudspeakers its the design and parts used that maters most the ohm loads more a issue when selecting amplifier.

A designer would need to invest more in drivers for higher ohm designs. Not alot of cheap 16ohm transducers about even in pro audio they cost more. But many cheap 4 ohm and 8 ohm transducers. The designs that are not Hi-eff are the far more compramised designs. They are designed to fit so many per pallet as much as sound quality. The profit margines are consider as much as performance. They have to apeal to many and must have hi SAF plus be easy to stock ship. Hi-eff designs are built mostly by small companies who realy care about end result. Since they move very few units they need to realy care about what they do since the moneys realy not there you get a labor of love so to speak. Or you can buy a 4-8 ohm design built in China with a vaildated audiophile aproved name. You get cheap MDF cabs and weak motor drivers. These will be placed in small bookshelf or slim towers with multiple woofers. Boring....

Unsound you said [I suspect that many speakers that are designed to be more effecient are in fact not so due to inherently superior drivers or other design parameters but, done so that they can better accomodate particular amplifiers and that course of action might just very well compromise the ability of the very speakers themsleves] You can have this opinion all you like but if you understood even a wee bit about transducer or loudspeaker design you would understand how wrong you are.

I dont think 4ohm 8 ohm 16 ohm are the better or only choice. Just a choice and a quality loudspeaker can be made at 4 8 16 ohm without any real issues but of course you need to select amp and loudspeaker that work well together. So the Ohm loads not much of a design issue more of a system matching issue. But for hi-eff I shoot for 16 ohms. for med 4ohms is fine and I offer 2 4 ohm models. As for the rest this thread puts a hurt on me brain so good day.