These types of places absolutely exist but while outsourcing might see a net gain I think they'd see an even bigger gain by getting rid of the dead weight and hiring people who aren't so stale/set in their ways. As in this is a failing of management and not something that outsourcing really "fixes".
It's been my experience that companies are not willing to make these choices. I'm not saying "Bob had a bad week, let's fire him" or "Tom is going through some personal stuff and his work has slacked, let him go" but rather repeated failures with attempts to rectify them with the employee that aren't fixed. The bar to let someone go is absurdly high at some places and kills motivation for people who are doing the work "Well, John isn't doing any work and the company don't seem to care, I guess I'll stop caring as well and just coast".
At my last job I had a coworker who refused to pull their own weight. We had the same title and I (and others on the team) were producing 3x+ what they were (when this team member even did anything, 3*0 = 0). Repeated complaints to our manager fell on deaf ears even with irrefutable evidence of this team member doing practically nothing. Some weeks they would move a ticket between statuses and that was all they did, no comments, no commits, no PRs, no reviews, no testing, nothing. Some weeks there was literally 0 activity by them on any of the tools we used and they were always distracted/distant in meetings, hardly contributing at all. That wasn't the only reason I left that company but it was one of them.