Nose rings are not indecent in that way, but in Somali culture, it signified slavery - slaves owned by Somalis had their noses pierced up to around 80 years ago. Indian slaves had their noses pierced by the Persian Mughals, and Hindu women would have their noses pierced upon marriage as a symbol of being her husband's property. There is even mention of nose piercings being used to identify slaves in the Bible. It wasn't until it was popularized in the west in the 1980s and 90s that it lost its stigma in other places, and by the 2000s it had become an innocuous accessory
Interestingly, the Hindi word for nose piercing is "Natha" which is derived from "Nathna" which was the act of piercing an ox's nose and putting a rope through it to guide it
Some Somalis disapprove, but so many girls have them now that the meaning has changed completely into something innocent
Doubt it. All my Asian friends have their nose pierced and most are unmarried. It is simply now part of their culture. Also, it isn't just a hindu thing as all my Asian friends are British Muslim Asians.
In their culture, the bride wears a big nose ring on her wedding day. It is from what I have gathered now just a symbol of adornment. Maybe historically, it could have meant something else, but for atleast generations it is something women beautify themselves with.
Also, there is different types of nose rings. Septem piercings have a slave origins not the nose piercings in which someone pierces the side of their noses.