Some time ago, when high resolution desktop screens (like 4k) were still relativly new, Spotify had some problems with the fonts in the Windows desktop version leading to pixly and ugly user experience. This issue was solved, and has been solved for quite a while, but has now reappered. See screenshot.
It looks like Spotify uses scaled up low quality bitmap fonts instead of truetype ones. I have tried to reset zoom, restart and reinstall the software, but the issue with the pixly fonts still remain. All other desktop apps show nice and smooth fonts.