Paul Graham, The Hundred-Year Language
Somehow the idea of reusability got attached to object-oriented programming in the 1980s, and no amount of evidence to the contrary seems to be able to shake it free. But although some object-oriented software is reusable, what makes it reusable is its bottom-upness, not its object-orientedness. Consider libraries: they’re reusable because they’re language, whether they’re written in an object-oriented style or not.
I think that comment jibes with my experience; objects are useful for particular problem-domains, but divide-and-conquer, building up a set of tools (functions) that each handles a little bit of the problem and putting them together in a much simpler framework – this is useful anywhere.