That's true, but when someone mentions writing something in an "imperative style" I think it's common for that to actually just mean one huge file that executes

That's true, but when someone mentions writing something in an "imperative style" I think it's common for that to actually just mean one huge file that executes sequentially which is not amenable to testing, having someone else working on a different part of the code without running into lots of merge conflicts, makes it very hard to refactor, etc.