This is an interesting thread. I thought too the overall popularity in tattoos and nontraditonal piercings was due to Pluto in Scorpio. I haven't noticed any big difference in tattoo prevalence in the last few years but I do know a lot of milennials have tattoos, a lot of my coworkers around my age and other people I know my age (I'm a milennial) do too. Maybe Uranus in Aries plays a part too. Myself, I have 5 ear piercings and just got my nose pierced. I've been flip flopping on getting a tattoo for a few years now but just recently have been more serious and had a consultation. My sun was conjunct transit Uranus a few months ago and will be when it goes direct again (it's at 29 degrees Aries). When they were closer I got my nose pierced somewhat on a whim, although I wanted to get that done for a few years now. That's just me though.
Neptune is in Pisces, maybe people are also being more artistic with their bodies? Neptune is trining milennials' Pluto in Scorpio too. Added to impulsive Uranus in Aries. Transit Neptune is also sextiling the Uranus Neptune in Cap conjunction around my birth time.
I still know a few people in my age bracket who would never get two ear piercings let alone a tattoo. I think it depends on the whole natal chart. That being said I think they're becoming the minority.
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