Agreed, as things get easier you need fewer accountable people. Organisations will shrink, people will be more accountable by themselves for things they ask the agent to do instead of having an accountable person do it for them.

On the other hand, I think for complicated software there is such a long tail of things that can go wrong, and in your linux example with disastrous consequences, people will pay good money for a long time to have someone who they can call if there is a problem. In the business they have the term indemnification - that's what companies like redhat provide for linux for example and it's probably a big part of what makes them a billion dollar business.