Reading through vintage fanzines again recently, from roughly 1975-1979*. The overwhelming majority of scenarios and descriptions of play fall into a “dungeon” or “challenge-based play” category. The descriptions of play read more like a sporting event recap, as opposed to a story; though both types form narratives, the former has less of a classic story structure, and the beginning & ends correspond mainly to start and end of a play session.
More than story focus, at least in A&E, I see a lot of of rejection of perceived arbitrariness of D&D mechanics, that drive toward things like spell point systems, smoother progressions, elimination of weapon & armor restrictions, and, well, RuneQuest. Like way more of this than anything about story or even just “acting in character.”
I fully admit to selection bias, being drawn more to the potential sources of challenge-based play. So take that with a big grain of salt. Someone looking to find more story support might want to examine early stuff related to The Chaosium: Wyrm’s Footnotes, for example. Pretty sure you can buy all those on drivethru. The Elusive Shift probably mentions plenty of other sources; haven’t read it yet.
* another bias is that a sizeable fraction of the zines are from the UK. Probably a disproportionate amount relative to the number of players in the US vs UK. Could probably substantiate that based on convention attendance records.
Anecdotally, I feel like UK D&D output started tilting more toward story around the same time as US output: Tortured Souls and/or Beast Enterprises stuff that eventually became the Doomstones scenarios; and some of the TSR UK modules. But this is pure feeling without any real analysis.