If you want to rile up most RPG designers, tell them “rules don’t matter”.
But, occasionally, players do say this. I think they often mean perfectly understandable things:
• Rules lawyers make my table worse, and rules arguments and systems/edition wars make my online experience worse, therefore I hate rules.
• I don’t even know the term “freeform play” exists, yet it is what I actually value about the roleplaying.
• Setting, theme and/or strong adventure plots drive my purchase and play decisions, not rules.
• People who say “I loved playing Ars Magica for a decade, but it is a lousy game” are not being nearly as clever in arguing for the importance of rules as they think they are.
• My “generic” system (Fate, GURPS, D&D, Empire of the Petal Throne, Bunnies and Burrows, whatever) is good enough for my purposes, your bepoke system isn’t worth the cents of electricity it would take for me to read it.
• I reject the claimed continuity between explicit rules, “rules” of style, and “shared understanding at the table”
• Rules provide a minor oracular compliment to my agenda as a player; therefore, I want them light.
• I hate the way the rules I’ve encountered limit my descriptive freedom to accomplish my goals.
• Ummm, many RPG designers keep talking about how you aren’t raking in the Benjamins, and lots of us players keep telling you that rules aren’t the most important thing, yet you focus on….rules.
• if I want a structured experience that applies rules to achieve an aesthetic end, I will play a video game, thank you very much.
• Watching actors and improvisers stream playing D&D is much better than playing myself.
As for myself, I think that rules clearly matter, and that this can easily be demonstrated by trying to play an rules set that that badly suits the genre of story or the creative agenda of the players at the table.
That being said, I believe the trend in the RPG creation community is imbalanced in valuing game mechanics over narrative design. Story, adventure, setting, and art direction are more than equal partners in creating meaning. Luckily, we can all make the games we want, and it is easier than ever to make them available to people.