I’m trying to follow the logic in the article. The discovery of bras told them that the Middle Ages were more liberal than the 18th and 19th centuries. How do they know these bras were indicative of anything? Maybe they were the only ones. Who knows? I suspect underwear was primitive. Period.
well, having studied history, I may be able to help here. Follow if you can: It’s the medieval era. You are a woman and live in a castle. You share rooms with other people, some you may not be related to. You bathe and change clothes (when you do) in front of these other people. You wear a bra for these events but no panties. This is less liberal sexually than the Greeks and Romans (who let it all hang out regularly and had sex in the common rooms of their houses with other people around, probably all through their rise and fall) but more liberal sexually than the corset-wearing bodice ripping renaissance when lingerie was developed and women only bathed and dressed in front of other women - many times only close relatives, who probably don’t share your room.