System and rule
The more time I spend in OSR/NSR conversations on the internet, the more I'm struck by the quietly contested state of system in those communities. On the one hand, there is an absolute welter of rulesets out there, ranging from relatively true-to-model adaptations of various editions of D&D, to radical reinventions of the form. But at the same time, there seems to be a broad consensus that none of these systems are essential to actual play. They're taken more in the spirit of suggestions. At best, each is a tool shed that may be ransacked for parts.
There appears to be a general aversion to playing games “as written.” GMs certainly haven't stopped bringing new games and supplements to the table, but to hear them speak of it, many run those materials using not the printed rules, but rather bespoke systems, hacked together out of elements from here and there. One designer of a well-known horror/sci-fi game is even said to have admitted he doesn't run his own game as written.
This makes conversation tricky. To what extent are we talking about the same activity when we discuss a game we've both modified, each to our own tastes? I'm reminded of the comment sections underneath recipes on food blogs: “Loved this dish, made it with turkey instead of beef, added oregano, and used a different cooking method.” Serve whatever you enjoy at your own table, but those changes complicate how we talk about what the recipe does or does not achieve.
The attitude shapes design as well. New games are routinely presented as hacks, by which I take them to mean a formalization of their own approach to running some other system. Some are written on the assumption that players will pick-and-choose which rules they'll implement. Maybe that's merely realism about the state of the hobby. In some cases, it's almost reads like a moral imperative. For people just cutting their teeth in the hobby, it can pose challenges.
There are, of course, historical reasons for these tensions. GURPS, heartbreakers, the Arneson–Gygax rift, D&D's release of a SRD. Ours is a haunted hobby. Cumulatively, these points along the last half-century of its development have contributed to a conception of system that suggests some underlying game we're all playing, an unattained object toward which this endless proliferation of rules is aimed.
Many paths, one destination. For me, that premise locked into focus a while back when someone on Twitter (I don't recall who) alluded to the “one perfect system” every GM is seeking — a semi-mythical ruleset particular enough to suit your own personal play-style, but flexible enough to accommodate any setting or story you might want to explore.
Deliberately or not, that trope correlates to a certain diminution of the rules. What function does a rule serve if you can change it out for another and ostensibly arrive at the same game? Are they even rules once they've been made interchangeable? At the far end of that trajectory is free kriegspiel, which dispenses with most rules in favor of judgments. All well and good. Your table, your rules. Or no rules, as the case may be. In the middle ground, though? The territory between D&D and FKR? Rules appear to have been replaced by system.
Would it be uncharitable to characterize the OSR as a movement built on devising new systems for playing old games? Perhaps; but it's also true that one standard by which OSR systems are judged is their compatibility with existing modules. That, in itself, exerts a formative pressure on design. It favors rules — or are they methods? — that do what has already been done, or which, at the very least, ensure that past modules, some of them nearly half a century old, don't break at the table.
Which is not to deny that there are innovations in the ever-growing catalog of new games and systems. There are substantive differences between them, even if the changes are sometimes incremental. But the demands of adaptability and modularity ensure that many of them are disposable. New games are made to be functional without any given rule or method because the odds of the system making it to the table intact are low.
I'm painting with a broad brush, but only to highlight a general trend. There are, of course, a great many games that take seriously the constructive power of a clever rule. There are games that daisy-chain a slew of well-crafted rules to foster novel modes of play at the table. There are games with rulesets so carefully calibrated that removing any one rule would undermine how the game as a whole plays. These games sacrifice the ideal of a universal system that can be used to role-play in any world, but in doing so, they make it possible to role-play some worlds and some stories better.