What many of us need and want is a modular productivity/creativity desktop computer that does not have an attached screen to it and is better than a Mac Mini, both in performance and user/manufacturer upgradeability. I couldn't care less about dozens of PCI slots or 3.5" HDDs but I am not buying anything that comes with soldered RAM and storage.
By us, you mean the "pro" community, which makes up a small proportion of the overall Mac user base. And I say this in air brackets for a reason.
I am aware of the rumours, but I am still not convinced Apple will release a mid-tier headless Mac, and I am even less convinced that creating one is justified. The iMac is going to be more than enough to meeting the computing needs for the majority of desktop Mac users. It has a gorgeous display (probably better than 90% of the monitors that people are going to buy anyways), is easy to set up, takes up fairly little desk space, is fairly quiet, and the fact that its ram and storage can't be easily accessed and upgraded is just not going to matter to many people.
In short, it's the epitome of Apple's design-led culture when it comes to the Mac.
If I were to look at this issue from Apple's perspective, I would argue that a mid-tier modular Mac doesn't make sense, for the exact same reasons you want one. The uproar over the price of the Mac Pro has further confirmed my long-held suspicions as well.
Take away the desire to use your own widescreen monitor. Take away the desire to upgrade the ram and SSD yourself after the purchase to save a few bucks. You basically have the Mac user which Apple has little interest in serving, both because it's already a fairly small market, and because well, margins.
It's becoming increasingly clear that a lot of the perceived demand for a "pro Mac" was really borne out of a desire for a "hobbyist" Mac, ie: one that you could open up and tinker around with. In the past, these two terms could still be conflated, when even the most powerful PCs were barely adequate for "real work".
But over time, as technology improved more rapidly than computing needs, standard off-the-shelf PCs became more than capable of meeting the needs for 99% of computer work, even for heavy users. But what frustrated the latter wasn't performance, but that these PCs came in sealed, untinkerable boxes.
The Mac mini is there for people who want to dip their toes in the Apple ecosystem. The Mac Pro is there for people with computing needs more intense than even the iMac Pro is capable of handling. The iMac is
the general purpose desktop Mac for the masses, and if they didn't run out and purchase an iMac Pro on Day 1 out of sheer need, they don't need one now, and they most certainly don't need a Mac Pro.
But with Jony Ive out, who knows.
