teceem: But in this context a third party is involved (Microsoft), and GOG has no contract with them concerning the evolution of their Operating System.
clarry: Doesn't matter. It just means that GOG has to do the work to ensure the game works, no matter what changes Microsoft does. If they can't, they give a refund.
Guarantees that involve third parties are nothing new. For example, there are aftermarket printer cartridges and the maker guarantees it works with your printer, and they guarantee it does not void the warranty of your printer. The printer maker is not and need not be involved in such a contract. It just means the maker of the cartridge assumes any liability and if there's a warranty case that is resolved as a fault caused by the cartridge, then the cartridge maker offers a service equivalent to warranty (i.e. replace or fix your printer).
Insurance works just like this too. You can get insurance against damages caused by third parties. It doesn't mean the insurance company has to make a contract with these third parties. It just means they resolve the damage if and when it occurs.
Yeah, except we can't say a microsoft update damaged the software.
That and GOG just might not be able to keep up with the upkeep if things break badly enough.
clarry: Understandably tech companies that deal in commodity consumer products don't want to take on such a liability, although it might not be as expensive as you might think. (How much can you claim in damages over not being able to play a videogame you got for a few bucks?)
That is, by the way, part of the reason our supermarket shelves are stuffed with cheap plastic shit that breaks and breaks and breaks. Yes, someone's responsible for the warranty, but as long as they can just keep replacing the shit with another cheap shit or say "okay, fine, have your three pennies back", there's very little incentive to produce a quality item that lasts. Taking them to court and claiming damages would almost definitely be far too expensive to be worth it, if the court doesn't laugh you out. A class action suit could work but these take a lot of effort to organize and require a large enough riled up population.. usually people don't get that riled up unless it's an expensive item they're having difficulty with.
Injunction. Sure, no one's going to sue for 5 bucks back, but they can sue for an injunction that would obligate GOG to make it work, or face a bigger fine/payout.