i would be interested if it is the case but i doubt it.
I can't see it being at all plausible as a reason.
Any instance where the CMDRs present are in different ship types already has to load N different skins, any instance where the 23 Python CMDRs present all have different paints (even assuming that recolours don't count, and no-one has any limited-edition or no-longer-sold options, I think that's the number of different styles currently available) has to do the same, they still have to support in-game all the previously-sold ones anyway, instances with double-figure player counts are extremely rare regardless (but instances with double-figure
NPC counts, which apply the same texture loading burden so long as they're in a mix of ship types, are very common), ED's multiplayer performance - while still shaky - has improved over the years as the number of cosmetic options has also increased.