This comment[5] from a Debian developer seems an excellent summary of the issue:
"It's fine to show a woman in underwear if you try to sell women's underwear […]. It's not ok to show a woman in underwear if you try to sell a chair (and the scantily clad woman is just decoration / an object to draw attention to the ad) […]
"It's IMO fine to talk about and show breasts in a game which teaches the names of body parts to children; or in an app that helps women to detect early warnings signs of breast cancer; or (Ian's example) in software controlling sex toys; etc. Because there they are simply on-topic.
"And it's IMO not ok to use the boobs theme for a web scraper or other software unrelated to boobs themselves, where its only function is to make a small group of users giggle while objectifying, offending or boring the rest of the world."
[1] https://git.weboob.org/weboob/devel/merge_requests/228/diffs
[2] http://laurent.bachelier.name/2013/12/weboob-the-asshole-det...
[3] https://git.weboob.org/laurentb/devel/commit/e4ed7bf8e384f4a...
[5] https://lists.debian.org/debian-devel/2018/07/msg00428.html