Since I have updated to the latest version of XD, exporting to PDF's the quality has dropped dramatically. All my images are coming out low res. The text is fine though. Before the latest update my exports as PDF's were crystal clear. I have also tried to export to SVG but they seem to be corrupt. All I get is the SVG icon and no preview at all. The files average about 15MB but I didn't think that was a huge file? Correct me if I am wrong!
That is unexpected! Does this happen with a new file, or is it only on the file you're working on? If possible, we'd love to take a look at the file to see if there's something going on there. Could you DM me a link to an uploaded file (e.g. shared from the Creative Cloud, Dropbox, Google Drive, or similar service) so that we can look at it?