1. Continue the trend of safely covering the electronics on motherboard PCBs, SSDs, HDD, and other electronics so ESD handling practices become less critical.
Good points, though that was a sad thought about M.2 reliability issues.
2. More thought into signaling to what in the past have been "dumb" subsystems such as the PSU.
Exactly. If the OS could query the PSU's capacity and current load, then graphics drivers could limit the GPU to avoid overtaxing the PSU and triggering a random reboot. Instead, they could pop up a notice, telling the user that the GPU performance is being limited by their PSU and suggesting an upgrade.
I built a desktop Athlon system in 2006 that had ECC. Worked great.
Back in 2006, you also could build an Intel system with any CPU,
and have ECC. At that time, the
only requirement was to use a suitable motherboard. This was true until they moved the memory controller into the CPU, in the Nehalem generation.
4. Like above, add device statistics like SMART to detect failures are accumulating. If there are memory errors occurring at the same address, the OS should let the user know. If core 3 of the CPU keeps having to shut down on thermal and there no heavy load, the user should know. And SMART errors creeping up in the HDD should also be communicated to the user.
These are already possible, and even exist, to some extent. You're really just talking about software features & functionality.
And with regard to thermal capacity of CPU cores, this is already a done deal. In AMD CPUs, it's being monitored and the OS is steering work on the basis of which cores have the most thermal headroom. I know some Intel CPUs have certain cores designated for lightly-threaded workloads, but I'm not sure if they do dynamic monitoring and reassessment (though I'm sure they will, in the near future).
5. Subsystems should be "hardened" against cyber attacks. This means that the hardware philosophy should be to not trust the other hardware on the PCB. If your audio CODEC chip is trying to flash the firmware in your USB controller, it should not be allowed.
I think IOMMUs fixed this. I believe it's no longer the case that any device can simply write to any physical address, though I could be wrong about that.
What can the user do that is in hindsight not a good idea, but they do it anyway? Pick up a USB drive in the parking lot and plug it in - and it bricks your whole system. How: it dumps negative 200VDC into your +5V bus. D'oh.
I've certainly read about how
malicious USB devices can fry a host, but you don't get -200 VDC without a big capacitor and a DC-to-DC converter, right? You're not simply talking about a defective USB stick or one that's physically damaged?
6. I believe the PC industry should consider marketing to gamers and overclockers differently than to PC builders / hobbyists.
Do you think the non-gaming DIY PC community is really that big, or even growing much? I wish I shared your optimism, but all of the long-term PC market trends are headed in the wrong direction, even if the last few years have been decent.