I have been using this font for 3 years now. I can't, and won't get off it. I use it wherever I can - heck there's an Arch package! I'm pleasantly surprised by how much something this simple makes me happy. Legitimately a font has added to my life.
But alright, I realized you must download the archive to find LICENSE.md in there: https://github.com/be5invis/Iosevka/archive/refs/tags/v34.9....
The license is "SIL Open Font License, Version 1.1." from http://scripts.sil.org/OFL