My professional experience in microbiology is going to disagree with you. BV, whatever the cause (and there are several), predisposes women to STI infection, but you're free to believe whatever you wish. In fairness to women, yes it can be caused by dirty hands (I always wash my hands for 30 seconds before starting any session) and other benign choices (non-breathable underwear), but it can also be caused by douching or using wipes that disrupt normal bacteria flora. I've known more than one woman who doesn't know douching is not a good idea.
In more fairness to particularly SPs, it's an occupational hazard because multiple sex partners is a risk factor for BV, especially when unprotected oral is involved. Oral sex can make Fusobacterium, which is normal mouth flora, more hospitable to the two bacteria responsible for BV (Gardnerella and Mobiluncus)
Whatever the cause is, only antibiotics get rid of it. (BTW, it's very weird to mansplain a female condition to a woman, but the contention that there are no hygiene habits related to topic of discussion is just not always the case).
In further fairness to the woman, unless the case is as extreme as the experience I had above, a lot of people don't experience the distinct smell or discharge. The woman in the experience actually said out loud that it smelled like sex in the room, but I've had a lot of sex where the room didn't smell like a fish kill afterwards.
