Are we sure we're talking about the same thing? I'm not suggesting a freelancer can net $120k in a year. That's easy. I'm suggesting a freelancer can net $120k plus living expenses in a year --- a number perhaps closer to $200k-225k. The reason I think that I that I know a lot of people who do --- many of them outside my (particularly lucrative) specialty.

Practically every established consultancy in the US throws off numbers like that year in year out, as a routine. Which is one reason a lot of consultancies end up spinning up product teams.