> "Do not prematurely optimize" is not a software design rule, it's a time-management rule.
No, it's both. Optimization often affects the cost of later decisions, and the reason not to prematurely optimize is because it can easily take you to a local optimum which is not very optimal at all. This is a perfect example of that, as the GP comment point out. If memory is not constrained as it was when this trade-off became common, it may not have become prevalent. Static binaries are faster (the degree to which depending on a lot of factors), while dynamic binaries are smaller on disk and in memory, if the shared libraries are already used elsewhere. Modern optimizations at the OS level for forking and threading should make consideration of those negligible.
Dynamic linking wasn't invented as a premature optimization though. And if it didn't exist today, it would still not be premature to invent it, because dynamic linking does not only concern how large and fast your program is, but also how it is interacted with.
So here is my point: optimization that can affect the relevant interfaces of your software is not premature because deciding on the interfaces your software exposes is not premature.
You are choosing to focus on the "premature optimization" wording, which is fair, it was said. I'm focusing on "as a community would we choose to reimplement and universally adopt this optimization?" (emphasis mine). I think it would be implemented, I do not know of any evidence that makes me believe it would become universally adopted given modern resources.
I'm not sure exactly what was originally meant, I interpreted it as how currently dynamic linking is the norm, is used in every mainstream OS and most the applications run on them, and all the major mobile platforms. If we had to make a choice right now without the history of dynamic linking behind us, would we still choose to use it for the majority of platforms?
No, it's both. Optimization often affects the cost of later decisions, and the reason not to prematurely optimize is because it can easily take you to a local optimum which is not very optimal at all. This is a perfect example of that, as the GP comment point out. If memory is not constrained as it was when this trade-off became common, it may not have become prevalent. Static binaries are faster (the degree to which depending on a lot of factors), while dynamic binaries are smaller on disk and in memory, if the shared libraries are already used elsewhere. Modern optimizations at the OS level for forking and threading should make consideration of those negligible.