I have never seen any photos or videos of a Sherman in WW2 or currently with mudguards or those side skirts, I have never seen them, they only add weight and make it uglier, could you Gaijin technicians remove that side skirt from all Shermans?
Even if Gaijin removed them, I can guarantee you that the weight would not change.
The weight comes from primary sources and they just state a general weight value.
Seeing most Sherman models with full fenders is somewhat unnatural to me, since 99% of all Shermans had the small fender, only the earliest ones like the M4A1 and Sherman I would be correct.