Will come back with more later but i dont think anyone can disagree that they do serve a pretty solid role of tech preservation, even if its just offense/defense stuff and not medical supplies or other useful tech (this is a major problem House and the followers have with the BOS). If we are talking about the east coast brother hood at least for a while they were doing some legitimate good but we see them still being awful when you get into the fallout 3 post game dlc and see that they are either refusing to give water to certain places for no reason, over charging for it, or dick head members are stealing and selling supplies. Makes no sense when the whole purpose was "here is the massive water basin we can help the wasteland, oh wait we have to ration it now"
In fallout 4 it was made so much worse and they are even shitty at tech preservation because of their insane hate boner for certain AI and synths. Really not sure how little maxson turned into such a A-hole especially with both Sarah and Elder Lyons guiding him