Earlier quoted context omitted.
Don't kid yourself, there is nothing you can do to prevent people from 'stealing' code they are working on if they are working from home or any other place where someone is not looking over their shoulder 100% of the time. There are reasons to force people to work on a corporate machine, preventing them from stealing code is not one of them.
How would people steal code if they're on a corporate laptop and a VPN that blocks & tracks?
Or encrypt the whole repo and just send it to a bucket somewhere. I mean there's got to be a lot of ways to do it if you really want to.