If a studio on it's last legs is required to service a failing product instead of working on a new one the studio will simply close and not comply. That's what tends to happen with forced regulations like this.
If they're closing they have nothing to lose by putting the source code up on the internet and saying sue us if you want. It's continuing businesses who are scared of liability.
And it's what would have happened anyway without the law. How is this difficult to understand? It's not like it's only a few games that shut down without recourse for the players. Ross Scott already did the research on this. Something like 95% of all online games that shut down do so without providing any way for the players to continue playing in some way or without issuing refunds.