The list management strategy is guided by the game plan.
You don't build a list of random young players and then go "right, how do we make a game plan from this pile of bodies?".
Doesn't matter when the list management strategy was signed off, it was under a different game plan. There will be a new one but they can't figure out what it is until they have a coach.
Bit of column A, bit of column B.
Gameplan certainly should influence list management strategies, but ultimately you have to design your gameplan to fit the cattle you have. Coaches last what 3-5 years on average? Your key players should be at the club for 8-15 years. You can't be turning over your list every new coach that you have, you can make adjustments to the list, which is ideally what trade period is for, but the game plan has to be fluid. The best coaches are able to do this, the one hit wonders are often the ones who can't evolve/adjust their gameplan.
I'd agree that at the moment, without a coach, without a gameplan, its very hard to do any meaningful trading/list management. The list manager is there to monitor the list longer term and prevent coaches from compromising the future for their own gains.