Why would anyone want class AB amp when class A always sounds better ?

I can design a horrendous class whatever amp too. That's not the point. No, design is a lot but it is not everything. There are limits of what is possible.
Orpheus10, there are great SS preamps, they are expensive and one can probably do better with tubes for the same or less but I don't know it.
Boulder, Gryphon, D'Agostino, Soulution, Accuphase etc.

Yet another fine example of a tempest in a teacup.

Hey, y'all.  Let's visit each others' homes and argue about the color selections of wall paint, furnishings, each others' shoes....

...that dumb aze Porsche vs. a nice Cadillac SUV.....with all the options...

The latter strikes me as the most blatant offering of a pointless ego toy that will NEVER see muddy roads....perhaps a deep puddle @ the mall....the bumpy RR Xing that gets 'tippy-toed' over...

Give it a break....:(

Strange noboby is complaining about weight and dimensions of class A serious equipment.
I just gave away two clones of class A Pass Labs and I'm looking for a good traditional A/B amplifier, because I'm tired of turning on two blocks each time, having double waste of space (one block on floor and the other in the rack), having to move 38kg (83lbs) for each operation on every block for cables, cleaning floors, etc. The difference in sound is evident, as well as the inconvenience.
Just my experience.

Clearly, there are lovely examples of amps of all description. That said, I still occasionally hear old low watt Levinsen and Krell class A devices which move me to tears. There is something there. Options exist at my house but a Pass XA-30.5 remains an object of my most ardent affection.

The most difficult thing to discern is who listens to equipment, and who listens to music?

Ages ago when there were stereo stores all over the place, I fell in love with new speakers everyday. It's for certain I was an equipment lover then, but that's before I got into "The high end". My favorite tuner was "Sansui", it had a most beguiling sound that was quite soothing, and many people still prefer them to more accurate tuners.

My favorite speaker was first JBL, and next it was the Amazing Carver Speakers;
        https://www.stereophile.com/floorloudspeakers/290carver/index.html
The music had an other worldly quality; "ephemeral", I guess would be the one word description, but at one time I liked "reverb" in my car, that made your automobile sound like you were in a cave.

When I got into the high end, I finally discovered how good the music sounded unadorned without any tricks. Since most speakers have some kind of "sound", I had mine custom built to have no sound of their own, but to deliver the music, the same as a Class A amplifier delivers it to them; without anything added or subtracted from the music, only what the artist wanted you to hear, his music, with each and every individual nuance.

While I mentioned Class A because it is "Theoretically perfect", I can not audibly distinguish it from AB.

One of the problems of differentiating music lovers from equipment lovers, is that equipment lovers will almost never come clean and admit it (maybe they don't know themselves) consequently, right or wrong, I discern who is an equipment lover, and who is a music lover. This is very important when reading Posts.