I'd actually argue the "non-Pro" iMac fills that space for a lot of people. An 8-core i9 with a 1TB SSD and 32GB of RAM is $3600 (or ~$3200 if you buy it with the stock 8GB of RAM and upgrade it yourself, as that's one of the few Macs you can still easily do that with!), and that's a pretty serious computer. For a web developer and writer like me, it's arguably already overkill.
I think there's still a desire for a "midrange" headless Mac between the Mac mini and the Mac Pro, but that's been something people have wanted for many years -- it's pretty clear Apple doesn't think there's enough of an addressable market there to make it worthwhile. (I also think people underestimate how much power you can actually stuff into the current Mac mini as long as your work doesn't require a serious GPU.)
> An 8-core i9 with a 1TB SSD and 32GB of RAM is $3600
Whaaaat.
That's nowhere close to a reasonable price!
Playing around on PCPartPicker [0], I can get a 12-core Ryzen 9 3900X, 1TB SSD, 64GB of RAM (expandable to 128GB later) and a RTX 2070 Super all for less than $2k. Sure, the monitor is worth something - but 50 percent?
The same panel in standalone 5k monitor form from LG is $1300, and even the non-name-brand versions are still $1k+. There's still a bit of apple markup, but it's in the same ballpark when you include the monitor.
The monitor, yes, but also the case, the keyboard and mouse, the OS, and the luxury of you not having to build and image the machine. Depending on how you value your time that could be a huge savings.
There are many reasons to prefer the Mac. But in this comparison, you also have to consider that it probably not only has the better CPU (the iMac is overdue for an update with a more current CPU) and the better Graphics card, but the advantage that you can change grapics card and SSD easily any time you feel like doing so.
I do think that the upper range iMac is one of the best value Macs, but it still suffers from being glued together.
I am using a late 2015 5k iMac, as this was the only alternative back then. And if needed, I probably would get another high end non-Pro iMac. I would be much more excited about the iMac, if Apple had not glued the machine and I could access and exchange the HD in it. Also a big problem with all iMacs is, you are stuck with the graphics card you bought it with - and there was not really much choice back then.
Yeah, I'd like to see the iMac -- and the Mac mini, for that matter -- move back to at least somewhat more user-upgradeable. I'm willing to mostly forgive the Everything Glued Down aspect of the laptops (although even there they take that unnecessarily far), but there's not much reason both the RAM and the HD/SSD couldn't be more readily swappable on all the models, at the least. It'd be nice to have the GPU on a daughter card, too, even if it's something weirdly proprietary.
I think there's still a desire for a "midrange" headless Mac between the Mac mini and the Mac Pro, but that's been something people have wanted for many years -- it's pretty clear Apple doesn't think there's enough of an addressable market there to make it worthwhile. (I also think people underestimate how much power you can actually stuff into the current Mac mini as long as your work doesn't require a serious GPU.)