I was more thinking of it as a feature for publishers that don't have access to the original work anymore. Or, an option for the publisher to hand out the relevant parts of their servercode and have it made into a DLL so the game will always work offline / over LAN even when their servers are dead. Without having to modify their game in any way.
The hard part is repackaging the server code to run in a different environment, or to do the reverse engineering work to re-create the server logic. Both are likely to be more expensive than they'd be willing to fund.
But hey, if you can become expert in this area, maybe you can become the specialist. The one who breathes life back into our games from the 2010s when the corps are ready to sell them to us again in the 2020s. ;-)
Reverse engineering is at least a intellectually engaging way to make a living.