>>64011876 (OP)Sometimes, but it's a marginal thing.
Good accessory choices can win you an engagement which could win you an engagement which could win a campaign which could win a war. However, we're now 4 Maybes deep so we might as well say "Once Upon a Time an individual weapon won a war."
A better way of thinking is to look at the availability of weapon mods and the expertise of how they're used. Are there night vision scopes available for night fighting? 2x scopes for open fields? Reflex sights for close combat? Does the infantry know when to use them and when not to?
>>64011876 (OP)This, basically.
>>64011903Isn't that more about entire production runs of weapons rather than individual weapons?