This is certainly also true. But yeah I was very much thinking of the '80s, when a popular game could be simple enough that it could be cloned - a replication of all the game mechanics and gameplay experience, reskinned. (It’s still true, to some degree, with mobile gaming.) Generally speaking, I’m being at least slightly tongue-in-cheek when I talk about “stealing” game mechanics, but at the same time, I think modern game design approaches grew out of what was happening in the '80s and those early dynamics are still present, to some degree.
Working as a game designer, I do feel like too often we’re still more in “ripping off” than language of games territory, only now it’s a piecemeal fashion rather than whole games. Part of this is because the vocabulary of game design is extremely impoverished relative to film, but also it’s because we game designers are lazy buggers. Saying “we’ll do this mechanic exactly like in Game X,” is useful as a shorthand, and as a way of saving time avoiding designing certain systems, and it might mutate in the implementation, but… maybe not. Actually designing a game, without snatching mechanics wholesale from other games, requires an amount of time that’s just not in game budgets. So it doesn’t happen even when we really should be re-inventing (or at least re-examining) bits. This really struck me working on MMOs about a decade ago, when “World of Warcraft” was the hotness everyone was (absurdly) trying to dethrone (as if that was possible). There was so much “we’ll do this mechanic like WoW” (when trying to make games that were trying to distinguish themselves from it) that ended up creating a whole lot of games that played exactly like Warcraft, when the possibility space for what an MMO could be is so huge (and still largely unexplored). Although to be fair the problem is doubly bad in MMOs because no one wants to sink that kind of money into developing/publishing a game that’s completely untested in its mechanics (i.e. isn’t, as much as possible, a clone of a successful game).
Largely because copyright was never the applicable IP law to apply to game mechanics - patents are. Though yeah, they’ve thankfully not been used too often, though that’s probably because only big games have the kind of money to even think about patenting gameplay, and they also so rarely actually innovate. It’s interesting to see the ads that WB did for Shadow of Mordor around its “nemesis” system, which they patented, as you otherwise never see a AAA game actually try to sell itself based on mechanics…
Creative work, in any medium, is definitely all about riffing on what’s been done before. (I think, to some degree, that act of referencing even defines the ontological boundaries of that medium.) But to be fair, there’s dividing lines, and people absolutely talk about films “ripping off” (etc.) other films when there are incredibly similar plots and shot-for-shot scene remakes, etc. See discussions about Tarantino’s Reservoir Dogs relative to City on Fire, for example. The dividing line between theft and homage gets a work-out. Often the game industry feels like the relationship between early Tarantino and Hong Kong cinema, usually minus any of the self-awareness required for something to be an homage.
(And now I’m imagining the film industry working like the game industry, with scripts that read: “…Cut to: That scene from Aliens where Ripley…”)