R8000 vs R8050 (Di2) Groupset price

Is this a mech vs di2 disc? Or is this mech vs di2 rim? They could be comparing mech disc vs di2 hydro, also consider that they might be quoting a complete build; typically if you go stock you obviously have upgraded parts, so this could include wheels or some other accessory as well. If its mech vs di2 rim brake then yea its high. If its comparing mech rim to disc then that could be why the cost is so different. If its mech disc vs hydro disc di2, then that could also explain it.