> I tend to "print" a new PDF in hopes that it flattens the document. I wouldn't...

> I tend to "print" a new PDF in hopes that it flattens the document.

I wouldn't count on that. A well-implemented print-to-PDF feature will try to avoid rasterising whenever possible.

If you want to turn your document (whether in PDF format or something else) into a raster image, there are proper tools for that.