There are more devices than Android and iPhone, esp. some Android devices with higher lockdown. Additionally some of them either require Root or routing all your traffic through a VPN (either local or to some remote server) which costs battery and bandwidth.

>But I still don't see a need to pay any amount of money for the benefit of hypothetical visitors who already don't care enough to install a free adblocker on their phone.

You're not paying money for those visitors, you pay some cash if you need hardware to run a simple adblocker solution that protects all devices on your network instead of just the ones you can install software too.

>I object to the article making it sound like it's something everyone needs in their home, giving no coherent evidence and ignoring the real drawbacks.

Not quite, in your comment you object to the existence of a software based solution running on any hardware (though preferably on an RPi) over a software solution running in your browser.

The Pi-hole isn't purely restricted to the RPi and can run on a VPS or old laptop you have lying around.

Pi-hole can be easily temporarily disabled and I've done so to disable anti-adblock detectors in the past or debug some DNS issues. It's not hard.

There is definitely some advantage to setting it up for a family, on top of the advantage of protecting visitors, it's set-and-forget; I haven't touched our local pi-hole installation in about two years. It's essentially maintenance free.

I don't block so aggresively that all websites break, the only ones that break are cancer anyway and people begin to use them less so there is no point in giving these websites a free pass anyway.

For anything more I still rely on uMatrix due to finer control.

If you want to object to the average family having on of these you should consider formulating it other than "why buy hardware when I can install software?" because that's neither covering the argument not particularly convincing.