They're really just a sign of how weak general purpose computing has become. Almost all uses of Raspberry Pis for hobbyist projects could and should be done just as well with the computers that you already own and already have running.
:b
Dedicating a Raspberry Pi to running a DNS server is silly.
You could run it on your wifi router instead, or you could run it on the individual nodes. Either of those should be extremely easy. But practical general purpose computing has decayed (or was never really there?) so instead there's this silly PiHole thing where you just buy yet another computer and convert it into yet another special-purpose appliance because general purpose computing is so hard.
PiHole exists precisely because the Pi is a general-purpose computing device: it uses a relatively stock operating system and network stack to perform its task. Its competition here is not a desktop computer, it's a bespoke network appliance with custom hardware/firmware manufactured by somebody like Cisco.
What you lament is that so many of our "PC" systems seem to have wasted processing potential, but I think this is optimizing along the wrong axis. Sure, my desktop PC could run a home DNS server without breaking a sweat, but my desktop PC is not on all the time. Even the idle power draw from the ATX power supply likely outweighs the full-throttle power usage of a Pi-equivalent device.
Home computing (PiHoles, routers, and "smart home" devices) are a devolution of computing to commodity status in the same way that the PC was a devolution away from a mainframe-and-terminal environment. I think further progression along this axis is inevitable, and we should welcome entries like the Pi or this VoCore that keep the ethic of hackable, general-purpose computing even in a commodity footprint.
That's not my lament. I don't care at all about not wasting processing power.
I care about the fact that it's so difficult for people to use their existing computers in ways that were not intended by their manufacturers, that even technically adept people will just buy a new computer rather than deal with it.
It should be easy to install some new software on any of your computers (router or desktop or TV or phone or whatever) and have it do some useful new thing. But it's not.
I disagree. I don't think it's difficult for compute-related tasks (gpio now, that I'll grant). However, installing this sort of think on a desktop PC is more likely to be bespoke just because of the near-infinite range of user configurations and customizations. The PiHole works as well as it does because it's a uniform base without being a walled garden.
You want me to run a full pihole on my TV, laptop, phone, tablet? I have to administer all those and deal with the headaches of installation on all of those (if even possible in jailed envs).
You say it should be easy, have you ever done it?
Who says I'm just running a pihole on that too, you're making a hell of a lot of assumptions here. It's a media server, ssh bouncer, tailscale node and a lot more.
Firstly not all ISP provided routers are even flashable with OpenWRT, so how the hell do you install something on there to start with?
I have a hAP.ac from Microtik, I flashed myself by PXE booting the OpenWRT images, not an underpowered router in the slightest, it just doesn't have enough RAM to load the lists needed, as I said. Connection state tables in SOHO routers don't need to be large, so why need all the RAM, their inteded purpose wasn't soley to run after market, home hacked, heavy memory intensive software.
You know, if you'd actually attempted this and had some valid point, I could take you seriously, but you seem to ignore everything I said, like I run multiple things on the Pi, or I'd have to keep the PC on 24/7 and the idle draw would be more (electicity is expensive here), or how I can just magically install pihole on any router, then why is my router not 'powerful' enough.
Yes, I want my router to be an appliance, not something I need to curate, like updating my PC or laptop with the latest and greatest packages. I want it to be a dumb box in the corner (with security patches when needed) but I don't want to be messing with it.
I have a Pi to mess around with things I want to run 24/7 but not take excessive amount of energy in doing so.
I do in fact run everything on the same machine as my wifi router: http://catern.com/computers.html
A Pi 4 costs more than a second-hand tiny i5-4700 series with SSD and 8GB of RAM.
Still the Pi has GPIO and PLLs which Intel-based boards don't have.
For a comparable option, consider one of the Pi-Picos, Arduinos with VUSB, or a USB-Serial board with extra GPIOS.