This is ignoring the fact that the main reason retired phones are e-waste is proprietary firmware blobs and locked-down systems preventing users from maintaining their phone with security updates, and very limited support length from OEM's leads to VERY insecure devices after they drop out of support.
You should not be connecting these old devices to an internet accessible network.
Google notably does well here with 7 years of support, but others such as Sony are 4 years, and Xiaomi on non-flagship devices are similar, or Samsung on their lowest budget models...
Obviously you'd have to replace the OS with an up-to-date one to use the phone as a cluster node.
But... if Google can do so if handed a random pile of old phones, then why would a consumer not be given the same option for their phones? If it works only for phones sold by Google once, same question holds. And applies to other vendors.
As you said: the "phone becomes useless just because OEM drops support" cycle needs to be broken. Well.. that and ability for end-users to replace batteries, screen, fix connectors etc.
Also it's unclear how data would move in & out of these old-phone-compute-nodes. USB-C? Article is a bit light on details there.
> This is ignoring the fact that the main reason retired phones are e-waste is proprietary firmware blobs and locked-down systems
Couldn't Google somehow fix this? Since they control the substrate (Android) and they would be doing it for their convenience
Exactly this. Few phones allow bootloader unlock let alone open drivers that can be brought forward to a mainline kernel.
The article seems to refer to a 2023 Pixel Fold as one of their candidates - I guess a good opportunity if those fragile screens get damaged but not a cheap used device otherwise.
Even normal slab pixel devices have limited support for true android replacements like PostmarketOS let alone cheaper 3rd party devices usually running Mediatek/Exnos SOC that have zero open docs or support.
Google has so much influence over the hardware manufacturers. They should do more.
Does anyone in the industry know why so much firmware is proprietary?