I can't say I'm surprised and I much agree with this. I've held many positions in both the private and public sector. While the public sector was always inefficient (honestly it was significantly worse than I pictured before starting...far far worse like you could easily eliminate hundreds of jobs without impact worse) private sector is pretty bad in many places as well. It's also amazing what networking can do to ge…
I've worked in a public sector department that was run like a business. It was a contact centre that provided information and assistance with various government functions, but to do so it, it competed with private sector providers at open tender for the business of those various government departments.
Of course, it had a massive price advantage, as it was a) small and focused and b) not required to turn a profit.
That aside, it was run like a business, because if any customers were significantly displeased, the clients could easily move to another provider. So the focus on quality was high.
It ultimately provided a quality service to users, cheaply. But, and this was the important takeaway for me, the person running it burned all of his political capital protecting this highly performant section of a ministry from interference from other mandarins within the ministry.
He was a good man, and he expended his career protecting efficiency in the midst of public sector "meh".
Anyway, my long winded point is that public sector isn't inherently inefficient, and private sector isn't inherently efficient. Any sufficiently large organisation sprouts a self-sustaining bureaucracy. Public or private. In my mind, it's merely correlation that public sector organisations are typically inefficient. The causation is organisational complexity (that is, a large strata of middle managers)