The aim of proper punctuation is not just to blindly hew to a set of inflexible rules; it’s to clarify. In fact, that’s what grammar’s all about.
I bring this up because, as a sometime editor, I too often find myself defending old-school practices like hyphenating compound modifiers and adding the serial comma. It’s not that folks don’t understand. They just don’t see the point.
The point is, there’s simply no reason not to employ the serial comma. And there aren’t very many reasons not to hyphenate compound modifiers. But there’s one big reason why one should: it makes clear your intent. The easier it is for someone to read your writing, the greater the likelihood that it’ll actually get read.
Which is sort of why one writes. Isn’t it?