> Can anybody make a strong case to me as to why are buffer overflows considered an issue in C when it takes like 10 minutes to write and test an array implementation that prevents that from ever happening?

That it's not a by-default and forced language-feature and that most developer aren't going to spend those 10 minutes when they need an array.

They'll just use the language-provided array-implementation instead. Which in C is very, very unsafe.