I could be wrong, and I should caveat this by saying I live 150+ miles away from the nearest MicroCenter, but I think the DIY system build has just gotten too extreme and too expensive for the average non-gamer. When I got into it back in the mid to late 90s, DIY was definitely about maximizing performance/$ first. You could save a ton of money vs. the average Dell or Gateway build, never mind anything sold retail.
With the advent of 3D gaming, you had to go DIY because the average pre-built system didn’t have enough power, cooling or expansion room for the best GPUs. But I feel like over the last 10 years with the rise of content creators and esports, DIY is no longer about maximizing perf/$ and become its own aesthetic—almost an aspirational hobby. Now you select color coordinated components, RGB lighting effects, custom formed water pipes etc. and can easily spend $5-$10K on a build. With miniaturization and perf/$/watt now becoming the standard equation for non-gamers, you’re almost better off picking up a pre-built desktop or even a laptop or NUC for most computing needs.
That said, for god’s sakes, we need better iFixit repairability scores for most pre-built SFFs and laptops especially. Framework is a great start, but I’m hoping to see more widespread adoption of CAMM2 for user-upgradable RAM and better eGPU options/performance with a dedicated port/bus capable of at minimum 128gbps.
It's been ages since the average person could save money building their own PC. The big OEMs have too much purchasing power for you to beat them by buying discrete components at
retail prices. Having said that, if you hunt deals or live close enough to Micro Center, DIY can still be a good deal.* The main advantage is that you get to hand-pick your parts, and don't have to settle for the OEM's often subpar offering (or big markups to get what you want). There are still a few gamer-oriented OEMs out there that will pre-build a rig with an ATX motherboard and PSU, although they do pad their profit margins a bit. CyberpowerPC comes to mind. Even Lenovo uses all standard components for their Legion gaming PCs IIRC.
* Usually you have to buy components at precisely the right time. If you just go to Amazon/Newegg and buy an entire list all at once, it's virtually impossible for you to save money. In fact, you're likely to spend more than a comparable pre-built PC. But again, the fun isn't exactly about saving money. It's about getting what you want, how you want it.
If you have desktop computers with lots of discrete parts, being able to troubleshoot and replace faulted hardware is still a very useful skill. Warranties last a year, extended warranties last three, and a the average computer lasts seven or more.
So I'd put it up there with things like "doing basic car maintenance" or "repainting your bedroom" on the list of useful skills everyone should have if possible.
The vast majority of people don't do any basic car maintenance anymore. Many people don't even change their own wiper blades, so forget about anything "under the hood" such as an oil change. To be able to troubleshoot a PC, you typically need access to spare parts. Unless you're a household with multiple desktop PCs in it, it doesn't make sense to have these parts lying around just so you can save money on repairs.
Furthermore, the PC industry is roughly 2/3 laptops vs desktops. I believe this includes all corporate desktops, so the percentage of desktop PCs in homes is rather small. For Macs, the ratio is closer to 4:1 in favor of MacBooks, and all those fruity portables are essentially non-repairable.
Many of us here can troubleshoot our own PCs, but a lot of that knowledge was acquired over a decade ago. It's just not that useful a skill going forward.