Right, which means people making my kind of music have few options other than to use equipment designed for an opposite type of music. That's one reason that vintage instruments are so appealing - not at all for nostalgia's sake - but because they tend to be larger and simpler, with an emphasis placed on the fundamentals of synthesis. There's no doubt about it that the instruments that would best serve my kind of music would be the Jupiter 8, Memory Moog, OB Xa, Andromeda A6, and so on. How I wish the modern equivalents of such instruments were available today! And again, that's why I'm still clinging to my P'08s and PEKs. The choices of companies for us are few - DSI, Modal Electronics ($!!!), perhaps Moog, and maybe a couple others. I get a sense that things will only get worse for my type of music.
But at the same time there's more than ever to choose from. Let's also not forget that most modern instruments cost considerably less than the flagships of the past, even if you choose premium models. And it's not that there's not much out there in the poly synth market: There's the Prophet 12, the Prophet-6 and OB-6 (modules if you'd like to use them with a bigger keyboard), the 002 and 008, the Solaris, or even the Kronos, which is nice if you wanna add FM or Physical Modeling for example. Specifically the first five are very focused in terms of design choices - certainly not complicated instruments.
Of course, the mono synth - and especially the affordable mono synth - market offers far more choices, since there's also more money to make. But even there you'd find a plethora of instruments that many wouldn't have thought of years ago: from the Sub 37, the Minimoog, the Pro 2, the Buchla Music Easel, the Odyssey (even full-sized as it seems), the TVS Pro, the single SEMs, the Boomstars, the Elektrons to the Dominion 1. And then there's still Eurorack, which opened a totally new market with hundreds of modules to choose from. The latter is not what you're looking for, but it's still part of a synth market that is bigger than ever before. And this doesn't even take into account all the alternative controllers, the iPad apps, etc. The point is, if you look at the whole picture, poly synths, or even only analog poly synths are just one little part of the current market. Add to that the fact that more and more people are abandoning traditional ways of playing - and I mean that in the most neutral sense - and that niche grows even smaller. And the casual players or session musicians tend to use rather generic machines, especially on the road. That's where you'll find all the Nords and Workstations together with mostly traditional players.
However, at least companies like DSI and Modal Electronics still offer considerably good instruments for the sort of hybrid purpose where synthesis and traditional playing meet.* And they may not even exist anymore if everybody would start to make analog or hybrid poly synths - especially the "big ones." Not sure if the release of the Behringer DeepMind 12 will change anything, but in terms of pure analog sound shaping tools it's rather basic and meant to be a synth for the masses in the first place.
I'm also not sure if you'd be entirely happy with actually owning a Jupiter 8, a Memory Moog, an OB Xa, or an Andromeda A6, as most of those need maintenance, which just adds to the overall cost. Plus: it's 20-30 years too late to pick those up for reasonable prices (minus the A6).
* I'm not so sure whether the combination of traditional playing/composing and synthesis has ever been mainstream or wide spread - amongst casual users that is (I'm not talking about film composers for example). After all, if you look closely, most of the players from the 1970s up to the early 1980s who played in classic rock bands where preset users as soon as they became available. The majority didn't necessarily embrace to dive into synthesis. If anything, most of them had goals in mind that led to the emulation of strings and flutes in the most naturalistic way possible. And when samplers came out, most of them where relieved.
PS: To close on a positive note for you: I got the impression that about 5 out of 10 reviewers were bemoaning the fact that the Prophet-6 and the OB-6 were missing the extra octave.