While intention might have been to last XX years, I am becoming
increasingly pessimistic about longevity of most electronic devices. A
crystal radio with an open air capacitor seems like the only good bet.
Between electrolytic capacitor aging challenges, discrete and integrated
circuit hermetic failures, cost or other inherent technical flaws, I fear
most electronics will become inert over time. Many of us have the skills
to identify and replace bits to extend the lifetime of many items. I only
hope the skills and suitable replacement parts are available as time goes
on.