This is a big ask, but many competitors to D365 already have this capability, sometimes from as long as 50 years ago.

In cost roll-up (Calculation) rather than treating ALL lower-level costs as Material, take their entire breakout and store it as several lower-level costs. The existing Material cost field would then only account for materials added at this level. Same separation for Labor, Machine and ALL forms of overhead. The total Material cost would now be the sum of This level and lower-level material cost. As a result, we can immediately see the full material, labor and overhead "content" of a finished goods. The total Labor and/or Machine cost, or Subcontract cost would now be immediately visible.

None of this "has to" change the way costs are posted to the GL.