DC v. Heller was wrong. Go read the context around all of the places where a militia is mentioned in the constitution. It’s a pretty clear difference from the world that DC v. Heller created.
Yea, there's a lot of history around types of militias, too (especially formal v. informal militias). The historical arguments were what got me on this: the 'prefatory' clause is pretty clearly there to point out that formal militias are allowed, and make no mention of informal militias.