I guess I don't get the premise of the argument. Given the chance would you remove some amps? I would 100% say no to that.
I mean, I guess I get the "paralyzed by too many choices" aspect -because that happens to me. If I was going to make that particular argument though, I would make it around IR's instead of amps. I know that I have no chance to go through all of those to even test them. I DO kind of wish they would be grouped into some sort of "sound families" to make it a little easier to hone in on what I am seeking. (clearer, thicker, muddy, brittle, - whatever.)
As it stands with IR's I sort of gravitate towards 5 or 6 that I know about (usually based on recommendations of a preset I hear and like. I won't filter through 50 IR's trying to find "the one" because I never will. The issue is that I am not well versed enough in what each crazy long IR name means, or what kind on tonality it would represent. I either go with a known IR or I just match the typical cab up to the amp head like I would if I bought a new rig from a store and maybe test 3 or 4 in that family. I could (personally, YMMV and all that) be fine with FAR fewer IRs than are available. Amps are a little different for me though...
For starters, there is the baseline advantage of "If I own this particular amp, I can replace it with this super awesome, reliable, stable, consistent, lightweight system and still have my amp, with the same tone, plus a bunch of adjustability as well as an entire collection of world class effects."
That right there makes the III marketable and a no brainer to a giant range of people. If I happen to own a Silver Jubilee (and I did) or a Bogner (which I love) or an Orange Rockerverb - then having it in the box gives me instant relief because I know what I know and love should be available to me. Can another amp make that sound? Sure, probably. But probably that is also true because of the insane level of customization and adjustment we have available to us on each amp. You can tweak that Plexi enough to get JCM like tones out of it if you work it over enough. (or to make one Plexi sound closer to another because in real life they are so different.) In the real physical amp world that might still work, but it would often be impractical, so starting with the right box makes life a lot easier.
Will I ever use all of the amps in the III? That's unlikely for me. But the point is that THE ONE that I DO WANT TO USE is in there... and it might be different than the one you want to use. I can pick my starting point and go from there, and I LOVE that about this machine.
It does make sense from a marketing perspective to have as many realistic amp models in the box as possible so that you can serve the fans of that amp. Theoretically, at some point when the tone and feel of all of the amps are 100% perfect and indistinguishable from the real world counterpart, and if you have made EVERY amp ever - then you are 100% the only solution the world needs. I don't see that ever being the case, but If I were invested in Fractal Audio, you can bet that would be my goal and line of thinking.
So.... can we get a Carvin V3 in here at some point? I like that amp.