Whereas in South Korea only licensed medical professionals are allowed to open tattoo parlors:
> The Korean Ministry of Health and Welfare considers the act of tattooing similar to medical procedures and deemed they should therefore only be performed by a professional with a medical license.
The FDA is not empowered to regulate medical procedures. Those are regulated by state laws and agencies. So even if tattooing was considered a medical procedure the FDA would not be able to regulate them.
https://theworld.org/stories/2019/10/24/south-koreas-imperil... good read. I live in Korea and have had a lot of my tats done here, people seem to not care much about the tattoo shops, at least the artists I'm friends with said they have no fear of prosecution.
> The Korean Ministry of Health and Welfare considers the act of tattooing similar to medical procedures and deemed they should therefore only be performed by a professional with a medical license.
https://en.wikipedia.org/wiki/Tattooing_in_South_Korea