One thing that&#x27;s missing from the comparison is that the Elliott 405 likely came with a full set of documentation, down to the circuit level, whereas Broadcom has kept much of the Pi&#x27;s SoC details proprietary.<p>In 60 years, archives and museums will still have great primary-source information on the Elliott 405 and its contemporaries. Will the same be true of the Pi? It&#x27;s easy to focus on the smaller, cheaper, faster, but it must be realised that a significant amount of openness has been lost; and not merely because computers have become more complex, but also because there are commercial interests strongly discouraging us from understanding the details of how these machines work.