system
Given the following post, respond as if you're commenting on Reddit:
human
[Fallout] How come It's hard to make new Plasma rifles for the B.O.S in 3, but I can build a laser mini-gun, a Fatman and an Alien Blaster modification in 4?
gpt
The Lone Wanderer was a random teenager, fresh out of a vault, with no real military or engineering experience beyond (maybe) some basic technical know-how. The Capitol Wasteland was essentially *obliterated* during the war, with very few technical documents surviving and even fewer factories still standing.

The Sole Survivor, meanwhile, was in the US Army, receiving actual professional training in a variety of topics, including engineering and firearms operation. With the Commonwealth being much less devastated than the Capitol Wasteland, assembling proper factory tooling is a much more achievable goal, and even then, making an actual functioning arms factory requires a *substantial* pre-existing logistical base.