I’m trying to maybe narrow in on the difference. Not saying they do exactly the same thing… but there are similarities, and mechanics producing results (which is how I see the idea of “driving play”) is one such similarity. So is “the players make decisions” that drive play.
I’m trying to home in on where the distinction you’re touched on actually happens.
I’m not looking to do that either. I think it may be table dependent. Or game dependent (assuming people adhere to the rules as presented for whatever game).
It seems to me that the outcomes of actions is where the distinction comes in, and your description above of GM setting up situations and players interact with them doesn’t touch on the outcomes of the interactions.
I gave numerous examples in the post of mine you originally quoted, of ways in which I believe modern mechanics can drive play and directly contrasted that with other methods. I'm really not sure what I can add or where you feel I've failed to be clear in the drawing the distinction.
The words we use can have many different meanings, depending on context and perspective, and I absolutely do agree that you could make a perfectly cogent argument from first principles that traditional mechanics also drive play. However, that hasn't been the way we traditionally described such mechanics and I'm not sure it's all that relevant to the actual points being made. As mentioned in an earlier post, I don't really care one way or the other about the actual terminology that is settled on, but it seems pointless to try and change the jargon at this point.
Pertinent sections of my previous post, where I feel I already addressed the questions you're now asking:
"the whole "success with a complication" as a central feature is one obvious thing to me. The mechanics are explicitly telling you, "the game needs to move forward and something interesting must happen at this point."
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"At a more basic level, the philosophy that "nothing much happens; the status quo is maintained" is an unacceptable outcome -- instead, any interaction with the mechanics must happen in such a way that doing so moves the game forward somehow.
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In a traditional game "the game mechanics themselves aren't intentionally being built to generate complications, challenges, dilemmas, demand action or what-have-you."
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"In a traditional game about political intrigue and fear of betrayal, the players make decisions, the rules ... provide outcomes, and everyone is just expected to play along with the premise. The rules themselves don't generate intrigue and fear of betrayal, they just assess what happens in an environment where those things exist.
"In a modern game, the mechanics might directly say, "you now need to make a hard choice: do you remain loyal, at a cost to yourself, or betray your patron in this matter?" Again, I'm not greatly positioned to elaborate on how all these mechanics might work, but my feeling is they would be designed specifically to create intrigue and fear of betrayal."
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"Note that, the participants' decisions actually drive play in both situations -- I'm not saying this responsibility is completely offloaded to the mechanics. It would be slightly more accurate to say that in the modern version, the mechanics mandate that play is always driven
in the direction of the theme, instead of leaving it up to the players to ensure that happens."