I understand pointing out that an upgrade failure should be expected when Ubuntu tells you that upgrades won't work, but I don't agree with calling the Pi a "device for experimentation". Not only it's used for serious applications in industrial settings, but some products are sold as... personal computers:

> Raspberry Pi 500

> The refined personal computer.

> A fast, powerful computer built into a high-quality keyboard, for the ultimate compact PC experience.

https://www.raspberrypi.com/products/raspberry-pi-500/