He's taking a much broader view. You aren't forced into that job, but how are you going to survive if you don't do some form of work that's accepted by society

He's taking a much broader view. You aren't forced into that job, but how are you going to survive if you don't do some form of work that's accepted by society as such? If people own essentially all the livable land on the planet, then there isn't really a way to retreat from society to live on your own terms. The owner of the land will eventually stop you from using it. So in a sense, you're being forced to participate in a human society to some degree, and forced to provide benefit back to that society. Consequences for not doing so usually end up to be having some form of violence or another done to you.