id.me is valued at $1.8bn and has more than 130m users and has "partnerships with 15 federal agencies, 40 agencies in 30 states and over 600 retailers".
Bit of a stretch to call them a low cost outsourcer. They seem pretty legitimate.
They are a private business in search of a problem that is unnecessary for federal and state agencies to rely on for idp and identity proofing services.