You mean "in which I pose the rather obvious strawman". What scaffolding? What is this mysterious "extra stuff" people give vague names like "scaffolding" to that I've never encountered despite programming in a statically typed language all the time?
And while it's valuable to talk about popular languages in terms of the kind of static typing people are likely to encounter... they also have really outdated static type systems. While you can argue that it's likely that you'll bump into Java/C/C++ when working with static types, it's pretty invalid to argue generally about static type systems using them as examples. Things have just come a really long way.
No, because the affordances and limitations of static typing are not the same as the affordances and limitations of static typing as implemented in Java/C++. You can't infer very much about static typing from statements made about those languages, and you can't infer much about those languages from statements made about static typing, so it follows that you can't freely substitute one for the other in these discussions.
(not necessarily directed at you personally)
If the function has to handle different types in different ways, you'd have to write it again anyway. Otherwise, you could have used templates.