My Polo GTI has LED headlamps and headlamp washers, and I don’t have the winter pack.
It's beginning to appear a bit random and the Germans are not know for that either.
Did you consider that there may be 2 different LED bulbs with different wattages that produce different amounts of light. Or maybe the electrics provide different amounts of power.

The regulations do say that the 2000 lumens only applies to the dip headlight lights. So if I'm comparing my headlights with the headlights on my parents Merc it would be for dipped beam only. I wonder does this all have something to do with the static cornering lights fitted to my Golf? This light is part of the headlight unit. So would this count as part of the dipped beam?
I know my parents Merc does not have this extra cornering light. This last winter, I was driving their new car on a narrow country lane at night. I noticed that it was difficult to see around tight bends. My wife's A3 has static cornering lights so I know what to look for. I checked and their Mercedes definitely doesn't have them.
Do any of the new Mercedes headlights have a static cornering lights?