I’ve had this issue today, including assets caching links to old images/paths. Very odd.
I did the usual empty cache, quit, re-boot put it still persisted. Ended up creating a whole new site just to start afresh quickly. It was an old project re-visited. Guessing it retains references on S3 by error.
I’ve also noticed redundant CSS styles exporting, with image refs and fonts styles long deleted. Mostly from ‘Body’ styles.
Anyway, if anybody has any pointers on scrubbing old crap from projects let me know.