Not sure how having downtime is an anti-competition issue. I'm also not sure how you think you can take things away from people? Do you think someone just gave them GitHub and then take it away? Who are you expecting to take it away? Also, does your system have 100% uptime?
Companies used to be forced to sell parts of their business when antitrust was involved. The issue isn't the downtime, they should never have been allowed to own this in the first place.
There was just a recent case with Google to decide if they would have to sell Chrome. Of course the Judge ruled no. Nowadays you can have a monopoly in 20 adjacent industries and the courts will say it's fine.