I don't know if you have any stats or facts to back up this claim. I'm a game developer and have worked 40 hour weeks for years and have a broad range of out of office friends and activities. I know many others the same.
I guess I can't argue with that even though it's 5 years old. In my experience the US is a little worse for crunching than Canada where I work. In addition mobile, social and casual game tends to have less crunch than traditional boxed retail games. I work in mobile gaming where different ages and genders are well represented.
I don't think game developers /know/ anyone who aren't colleagues. Much less have friends that aren't colleagues.