This post is prompted by yours. It contains some reiteration, and some responses to other things posted in the thread.
The OP sets out a particular goal for RPGing, based on a particular sort of critique of some "mainstream" approaches. The goal is to avoid
RPG adventures and campaigns that overwhelmingly take the form of a more or less complete script being written that covers all the relevant plot points and sequence of scenes before the players even enter the picture, to avoid
the PCs being pawns for other NPCs, while also avoiding
stories that are short and not very much interlinked with each other such as sandbox-y
dungeon crawling to hunt for treasures or explore the magical wonders of old ruins. The OP wants
ongoing conflicts with regular antagonists that
takes place on a grand stage and revolves around the PCs struggling in an ongoing conflict against groups of NPCs, and also wants
the players' ideas, plans, and decisions determining what path the story will ultimately take.
So suggesting dungeon-of-the-week sandbox play is not helping the OP get what they want. Nor is suggesting a GM-authored world or timeline, in which the players', in play, acquire information about the world and/or the goals of the antagonists that drive the timeline and thus potentially alter the timeline. I think the reasons for both these assertions are obvious: the former is a version of the
stories that are short and not very much interlinked with each other which the OP wishes to avoid; the latter is not a game in which
the players' ideas, plans and decisions determine what path the story will ultimately take because the GM's ideas about the world and antagonist timelines play a huge role in that respect.
The OP asks "What's been happening out there in the world of player-driven narrative games?" and the answer is
the techniques for achieving precisely the goals that the OP asks for were developed around 20 to 25 years ago, and are readily available in a variety of published RPGs. The systems I think of are HeroWars, Burning Wheel, Apocalypse World and MHRP/Cortex+ Heroic. Torchbearer might also do the job, although it's not quite as obviously suited to the "grand stage". I'm pretty sure Dungeon World could do the job, though I'm not as familiar with it. I don't know exactly what direction Cortex Prime takes that system in, but it's probably suitable too. Fate can also probably do what the OP wants it to. You (
@hawkeyefan) have pointed to other systems that I'm even less familiar with - eg Spire - that are suitable. No doubt there are dozens, even hundreds, of others, which apply various versions of the techniques that (as I've noted) are now a couple of decades old.
TL;DR: The OP asks a definite question, and there is a definite answer available. The answer is not relative to "playstyle preference" or "here's how I do it". It's a perfectly straightforward matter of fact.