The larger concern around contractors, which the article touches on a bit but doesn't really crack open, is that all incentives are structured around the contracted company firing a trouble employee instead of working with them. And by "trouble employee" here, I mean "an employee who has suffered abuse, up to and including actual sexual harassment, from the main company and its staff and could therefore cause legal trouble for the main company."
Protections at the interface of two companies, where the employee is not technically an employee of the main company, are thin on the ground and legally complicated. And whether intentional or not, this has the consequence of making a fertile ground for all manner of quasi-legal employee abuse.
I worked at a company where a contracted employee was sexually harassed by a full-time engineer, and the "support" she got from her boss was clear adavice to keep silent because if the main company felt the situation was too problematic she could cost everyone their job when the main company decided to contract out to another provider. Because that'd be easier for them than even confronting the full-timer responsible.
(... the videogame industry brings its own flavor of sickness to the table above and beyond these general concerns. While my friend was humiliated and depressed as hell about the situation, the reason the threat from her boss even held weight is because they would be there months down the road. A lot of game studios cut their contractors loose when the game is out the door; there's no job security to be had).