Also mandate upgradable software. I feel that outdated software becomes an issue way before dead batteries for most phones on the market. Most vendors don't seem to care much about software upgrades, especially on the lower end, and not all devices are supported by LineageOS / postmarketOS and co. I'm not even talking about (ok, technically, I am) how hard and scary it is to install alternative firmware on smartphones: unsupported rooting process that can brick your device, loss of your data while rooting, unsigned binaries distributed by unknown third-parties, broken warranty by using unsupported firmware… Vendors should be forced to sell either hardware that can be used with third-party software, or harware and software that is guaranteed to be updated for more than “up until the next shinny new device is out”.
To be fair the android rooting community is usually transperent. It's perspective of "scary" shouldnt be compared to jail breaking an iphone to get free apps. Also, most tutorial for rooting or just flashing firmware it's alwqys adviced to backup data, so fear of loss should be manegable.... one more thing, if you've reached the point of needing to root/change device software, do you really believe the company cares about your warrenty. I've known people with apple care go get their 5 year old mac books for battery replacement, to then get their time wasted with a lazy response of "sorry we don't covery water damage". When for a fact that device never experienced it.
If you want to get software updates (and you /do/ want it, even if you don't know, because of critical security fixes), you reach the point of needing to change the device software in only a few years (see, even Google's own Nexus line has a laughable software support duration: https://support.google.com/nexus/answer/4457705#nexus_device...). In the lower end, it frequently happens before the end of the legal warranty in some countries (eg. 2 years in France), especially with discontinued devices sold during sales. Worse, there's a frightening number of phones sold on Amazon that run an /already/ unsupported version of Android with known security issues.
Then, when you have the chance to have a device supported by some third party, you discover that you can't do backups without having to appeal to some wizardry with ADB and your phone in “developer mode” (when you even have that option), because you can't otherwise do proper backups without having rooted your phone /before/ having data to back up in the first place (ie. thus voiding your warranty from day one).
This is a huge problem. Every single one of my iDevices outlasted their software updates. Yet, I can still install Linux on a 20 year old computer and it runs fine.
