Article on Substack

I wrote an article on how system matters and how it can make a difference over on Substack.

Thank you for that. I have always felt that system mattered and have opted out of games with GMs I know to be good when the system is something I just can't stomach. However, the reverse is not true: I have never opted into a game with a GM I know to be bad just because I like the system (but I have been tempted to do so...).

Of course system matters.  That's how you play the game part of a role-playing game.  I have always thought that the notion that it doesn't matter is asinine and obviously untrue.  Here's a conversation I have seen many times.  Someone came in and criticized a system or some aspects of it.  Inevitably, someone popped up and said they had been using the system for years, that it worked fine and their players were "having a blast".  They pretty much always used that exact phrase.   People would ask them how they deal with this or that game system.  It quickly became clear that the system was "working fine" for them because they weren't actually using it.  This was especially common for Old World of Darkness games.  I'm not convinced that anyone actually ran oWoD rules as written.  I'm not convinced that this was even possible with the crossover games that everyone seemed to be doing.     

Good article, though I would take issue with the assertion that BRP games have a HEMA-based combat design. HEMA had a miniscule profile in the 80s, and I've never gotten the impression reading BRP games that the people who wrote them had much of a clue how armed combat works.

That minor issue aside, system absolutely matters, and I'd add an argument to your list, which I think is critically important and too often gets downplayed:

System Dictates Setting

What is possible in a system, its resource economy, the way it expresses characters, etc. all produce forces that exert a huge influence on the game world. This is the reason why all the various D&D settings end up feeling pretty much the same. it happens in a whole host of ways, but an illustrative example is the arguments about "low or high" magic in different versions of D&D. The fact is that there are elements baked into the structure of the game which naturally produce a high-magic environment. The ability to use magic is granted for free to multiple classes at character creation, with the expectation that most parties will have at least one or two magic users in them; that magic is essentially free to use; mid-to-high level HP pools can only practically be replenished by magical healing; monsters that are immune to magic damage naturally produce a proliferation of magic weapons; magic armor is necessary to keep up with the attack ratings of high level foes; the list goes on and on. At an even more basic level, the fact that the D&D rules are fundamentally built for dungeon crawling tends to produce a game world that's full of dungeons. You can homebrew yourself out of all of this, but at a certain point you've homebrewed your way into playing a different game, and then we're right back to "System Matters".

A very well put arguments.

It does seem weird there is a camp of people who seem to think it does not matter, period. certainly table and Game-master are going to be big deciders as to the quality of the game, but system still makes up one third of that equation.

And as well the good Gamemasters I've played under often picked systems that suited their style or philosophy implicitly. even if they never chose that explicitly.

Systems likewise tend to have assumptions baked into their design, if you want to play a investigative game, Gumshoe fits the bill, hankering for a dungeon crawl? any OSR game off the shelf will do you, and if you want to play a shit licensed property game, go with PTBA.

I ran into this really hard with games like City of Mists. You have two character sheets and a ratio of traits between them. It's possible to gain and lose traits, representing things like a character losing their humanity and becoming a mythic archetype trapped in the collective unconscious. You can't represent that with a conventional system where characters are composed of attributes, skills, and so on. But it works great at representing lightside/darkside shifts and anything remotely similar. A lot better than a conventional system.

Great article, The runner analogy is on point.
In my experience the "system doesn't matter" point of view is way less present now than in the late 90s / early 00s (and it's a good thing), I still hear from time to time stuff like "dice are only there to make noise behind the screen, lol" which irritates me.
The Consensus argument has, in my opinion more strenght that you give it credit for. It is, in a way, what makes the OSR a real thing : everyone begin with the same simple ruleset and make rulings as they come in play on the basis of a consensus.

Anyone who claims system doesn't matter hasn't played different games with the same group of players under the same GM.  Imagine the same group of people playing different board games.  One game does not feel like another even with the same players.  In that RPGs are a mechanism for creating an improvisational story with some degree of randomization, the same group of people is likely to produce a relatively similar 'feeling' from game to game, but the mechanics that dictate how you improvise and randomize can shape the process pretty heavily.  What does the system encourage/enable?  What does it discourage or outright prohibit?  Those variables make a difference in the end result.

We don't have to be strict "orthodox" adherents to mechanics but they set the tone for the game. Without them, we are simply engaged in cooperative storytelling. That is part of the game but not the main thing driving it forward. Pudit did a couple of videos covering this that I thought hit the point well.