Finding out gender early

I'm seeing a lot of women that are 12-15 weeks pregnant announcing the gender of their baby. Are that many women getting NIPT to tell them the gender? My obgyn doesn't do NIPT unless other screening tests show high risk of issues. Are they going off a guess by their doc or US tech? Are they using theories? Of course every situation is different but I'm just seeing SO many women announcing gender really early, too early for US to be accurate, since a penis-looking protrusion is visible in BOTH genders this early.