I've written a lot about the Mac Mini over the years. In 2014, Apple introduced a new set of models based on the Intel Haswell chips, and at this time, the make-up of the Mac mini as a product changed a lot. The directly previous version had dual- and quad-core CPUs available, could run two SATA devices at once, and had socketed RAM for easy upgrades. The 2014 version switched the storage to one PCIe device and one SATA device and changed the RAM to soldered memory. Needless to say, the reviews and commentary were near universally abysmal.
For a long time, I was personally a little bit mystified as to why they'd do this. However, if you look at Apple's whole product stack, it becomes clearer. I think the reason for this is that Apple designs and builds a limited number of platforms, and it puts those platforms into different enclosures.
The Mac mini was part of the same platform family that drove the old MacBook Pro products. These platforms all had dual and quad-core CPUs, socketed RAM, two SATA ports, and socketed RAM. The 2014 Mac mini is based on the platform of the MacBook Air and the new 13-inch Retina MacBook Pro. These platforms feature 15/28w dual core ULV processors, PCIe based storage, and have soldered RAM, both for physical reasons and so Apple can use very low voltage RAM.
When the 2014 Mac mini was released, there weren't any good 35-watt dual core Haswell chips that used the IGPs that Apple wanted. Quad-core CPUs were too expensive as a starter option, and switching the product to desktop CPUs is unsuitable. What Apple did instead was to switch to the platform used by the Air and the 13-inch-Retina-Pro. (I presume that this is pretty much a shared platform, even though there are a few differences in implementation on these products.)
For Apple to have made quads available, they would have had to deploy two different platforms into the Mac mini, one supporting inexpensive dual core CPUs (and featuring soldered RAM) and the other supporting more expensive quad-core CPUs, possibly a discrete GPU as an option, and supporting socketed memory. Or perhaps, the other would have used quad-core CPUs and still had soldered RAM, because that's what the contemporaneous MacBook Pros used.
Today, the situation isn't really a whole lot better. While with the Haswell generation, there were 35-watt dual core i5s that Apple could have paired with a terrible discrete GPU, with Skylake, there are no such chips, leaving us only with a single suitable cheap dual core chip to use at the entry level: The i3-6100H with Intel HD Graphics 530.
Skylake could be a point where Apple changes some of its practices. They have yet to release any Macs with Skylake that use an integrated GPU. They released new iMacs with Broadwell chips in them specifically to get IRIS Pro graphics. But with integrated graphics performance on Skylake having increased a lot perhaps they can change their Haswell-era practice of only using the HD 5000, IRIS 5100 and IRIS Pro 5200 graphics, especially now that a few more chips are available. For example, the i5-6350HQ makes sense as a Mac chip, because it has the IRIS Pro 580 in it. Note that Skylake is the first generation where there are quad-core i5s available on the mobile side, which makes the jump from an i3-6100H to an i5-6300H or i5-6350HQ a pretty reasonable one.
The biggest problem with the idea that this could be the platform Apple builds for the new Mac mini is that historically, they do not sell computers with i3s in them. Now, the i3-6100H is no slouch. It's almost certainly a much faster chip than the i5-4260U that the Mac mini currently uses. Apple could easily dance around the fact that it is a Core i3 CPU, perhaps referring to it as "Core processor", especially since they currently do not advertise the exact model numbers of the CPUs they use. (Unlike a PC system from Best Buy, which will proudly proclaim "Intel Core i3-6098P inside!" even if the particular chip they are touting is pretty bad.)
The other question is whether or not Apple will return to socketed RAM. One of the reasons that the MD101LLA is so popular is because it has just that: socketed RAM and a hard disk that uses a standardized connector. While the battery isn't something you can pop out on a plane, it can be changed, and in general, people know how to take apart the machine to service components that need it from time to time.
This year could be the second turning point for Apple. I'm sure they know best, both literally and metaphorically, what actual customers think of the revised Mac mini, and the move toward soldered components on much of the Mac product line. The Macs that have soldered RAM are good enough computers, but I can see why people want them to have serviceable components.
I wonder if it's not just really time for more people to move on. Taking a quick gander at the Hardware Maintenance Manual for the ThinkPads X260 and T460 reveal a system that is both thin and more easily maintainable than previous generations.
It's obvious that Apple cares deeply about its hardware, probably at least as deeply about it as their users do. Those users continue to buy Macs even though the hardware has become, as many would put it, "user hostile." I honestly believe that this means the user is nowhere near as hostile to the users as people think it is.
Nevertheless, we're at an interesting point because Apple could take the feedback they've been getting about the Mac mini and "The 101" to mean that they should build thicker, but more easily maintained computers, even at the expense of whatever battery life and physical reliability gains that a closed system might have.
I think the key is understanding whether or not the volume of posts on Mac fan web sites about this issue really translates to actual customer sentiment. I have my guess, and I'm sure Apple knows this.