Yes, but a lot of the improvement is coming from layout models and/or multimodal LLMs operating directly on the raster images, as opposed to via classical OCR. This gets better results because the PDF format does not necessarily impart reading order or semantic meaning; the only way to be confident you're reading it like a human would is to actually do so - to render it out.
Another thing is that most document parsing tasks are going to run into a significant volume of PDFs which are actually just a bunch of scans/images of paper, so you need to build this capability anyways.
TL;DR: PDFs are basically steganography
