I'm not comfortable with the idea of the government dictating what developers must do with their games. There are legitimate legal, financial, and artistic reasons they may not want to be forced to distribute in that way.
I think that it's the responsibility of consumers to make sure they have the level of ownership over the games they like. I personally don't really like to invest into live service games for this reason, but I do enjoy playing them on occasion and appreciate that they're free to play and receive constant updates. Forcing the Deves to open source their code at the end of the game's life cycle would jeopardize their vision and our ability to play games like them.