In this question I spent some time in comments with @detly to refine and clarify his problem for a possible answer.
With further clarification, I read the question again and had one of those moments: the problem cited is a symptom of the different problem, a problem related to @GMJoe's answer on in-game leadership, or at-table leadership, as a path toward resolution.
The fingerprints of the XY Problem were clear to me.
My assessment: Based on information provided, this group of half a dozen has not formed a team, and has little-to-no leadership.
This isn't necessarily a bad thing for TTRPG's. Our hobby is a fun activity where success is usually increased as a result of all contributing. Plus, peer leadership is one of the trickier bits of that art. Leaving theories of leadership aside, I did not challenge the frame. It was tempting.
First instinct:
Your problem won't go away, because what you describe is a symptom of a group that isn't a team, that hasn't got a team focus. Until you address that group dynamics issue, this symptom won't go away. An answer like that is a big time buzz kill. As I try to parse the norms and memes of this community, such an answer would be condemned.
Second instinct:
Offer a bandage for the sucking chest wound, here's the first aid kit. That's all the tool suggestion can be: a band aid. No idea how well developed the group's social contract is, or will become. (One hopes nothing but success on that score).
Justification/Rationalization 1:
The tool is the kind of thing @detly asked for. (Con - If I look at the XY Problem, it's not directly addressing what looks to be a root cause, and so may not be helpful).
Justification/Rationalization 2:
The teamwork / team building appeal may or may not work in this particular group. It may be beyond the social skills of the querent, the DM, certain group members, and all-in-all "too hard" to fix. This is a leisure activity, is "fixing" worth the effort and social risks associated with it?
All justifications (excuses?) considered, was it wrong Not To Frame Challenge once I recognized what looked like an XY Problem?
I ask this in part because I think @GMJoe's reply was a form of frame challenge, even if not explicitly identified as such. Gears began turning in my head after @Miniman's early comment that "this doesn't answer his question." I was tempted to comment it being a frame challenge, but chose not to for reasons.