It is not really a fair comparison. I would expect that an old android phone that is just sitting in the cupboard to be used for hosting. I think the goal should not be “hosting website” but to be able to repurpose an old compute device for something useful. Phones these days are really good computing devices. 8GB or 16GB RAM, fast and efficient ARM processors, flash storage, inbuilt ups, Wi-Fi and 4G/5g connectivity, gpu and hardware accelerated encode and decode for video codecs etc. An equivalent VPS (hardware wise) would be more costly imo.

Especially when the article suggests to "subscribe to Pinggy Pro", which is $5/month (currently $2.50/month on sale). Pretty sure that's more than the cheapest VPS on Hetzner.

This seems like paying more upfront and paying more per month for less.

Cloudflare still provides free hosting for one website. Setting it up not exactly straightforward. But they're currently hosting my website, my domain, and giving me free CDN, without my having ever provided a credit card.

You probably don't even need a VPS. Shared hosting still exists and will be even cheaper and still be good enough.

A VPS has the benefit of also giving you a static IPv4 which will then allow you to build your own tunnels and Wireguard stuff.

But considering the amount of RAM current phones have, compared to what you get with a cheap VPS, there might be a benefit of running it on the phone.

I've had a VPS since about 2013 or so and I think I haven't passed $180 yet. Of course it really depends on your usage loads, RAM usage, etc. But for small websites/apps there are cheaper alternatives.

You can get a free ARM VPS with Oracle Cloud at the moment