I have had this issue too!! Very frustrating. My work around is to save the PDF that pops up from the Shopify Barcode app to my laptop drive and then open. The quality is high as it should be. Then I print. A hassle but it works. I have a Rollo thermal printer used for barcodes and shipping labels.
I tried changing the chrome print settings- but they were fine. So annoyng!! Hope this helps!