I think piracy is the best method of preservation because it's removed from a financial incentive. Publishers just aren't going to spend a dime if it doesn't make a buck.
The problem is that piracy doesn't help for always online "games as a service" games where the game is killed after the server has shut down. You can't pirate the server because it was never available, and outside of being lucky enough that a few hackers dedicate a lot of spare time to reverse engineering it, that game is gone forever.
The point of this initiative is to ensure that game companies have a legal obligation that at the point of shutting down game servers they must either release the server software, patch the game to work offline, or do whatever else to ensure that the game continues to function.
It's worth noting that this would only count for games sold as goods i.e you paid a fixed fee at the time of sale with the expectation of owning a product indefinitely. Games with explicit subscriptions such as MMO's would not be subject to this since there was never an expectation of access to the product continuing after the subscription expired.
If I may be frank, most history isn't worth remembering. There will always be a dozen fans of some niche MMO that lasted a year in the 00's, but people just move on eventually. It's entertainment at the end of the day.
I would argue there kind of is such an expectation. Unless obviously stated in the game description before payment I would expect it to function similar to other games I purchased. And I can still play the offline games from early 2000s without any issues.
I'm saying that because if an online game would be sold with a banner like "we plan to support this game for next 3 years but it might shutdown any time after that" this would absolutely affect my decision to purchase it or to purchase microtransactions inside the game.
Doesn't Steam actually let people keep a game in their Steam library even if the publisher takes down the store page for the game?
Most games these days don't have a self-hostable dedicated server.
In case of Steam/Valve specifically it happened a while ago with Counter-Strike: Global Offensive. Valve replaced it with Counter-Strike 2, and while GO's client is still usable, some of its online components are not.
Another point is that Steam DRM is a) optional b) unlike always online GaaS trivial to circumvent
ToSes aren't legally binding when they require you to waive your rights. This has been tested in courts repeatedly.
It is worth noticing though that Steam has stopped using the word "Buy" and instead use terms "Add to Cart" and "Continue to payment" which are perhaps more ambiguous but still not much so IMO. They did however use "Buy" in the past and changing the store interface now should not excempt them from fulfilling the expectations they have set in the past.
Now consider how many of the modern classic PC games are kept playable/relevant (a problem with some older games are things like terrible playing mechanics; graphics less so) by an enthusiast modding community.
I don't think that's universally true. Paradox Interactive are a studio with grand strategy games, and even decades-old games still get new sales of the base game and the DLCs, with a strong user base.
this is not just a GaaS thing (though GaaS is the biggest in the list), even evergreen indie titles can choose to just add more content to a single player game for years instead of making a new title. titles like Terraria and Binding of Isaac more than passed a decade at this point.
In the EU it's a bit more complicated but I still don't see authors rights as a primary motivator for copyright specifically.