Complicating this analysis is that computers have still been making exponential improvements in capability as clouds became popular (e.g. disks are 1000-10000x

Complicating this analysis is that computers have still been making exponential improvements in capability as clouds became popular (e.g. disks are 1000-10000x faster than they were 15 years ago), so you'd naturally expect things to become easier to manage over time as you need fewer machines, assuming of course that your developers focus on e.g. learning how to use a database well instead of how to scale to use massive clusters. That is, even if things became cheaper/faster, they might have been even better without cloud infrastructure.