Ah, fallout 4 had so much Potential. In the older games the endings, the "good" ones at least, tell you how this and that community build itself up and thrived, due to your timely help.

Would've been nice to feel like you'd be doing the building.

Also it's good for all the money you can gather from the higher level enemies. You don't need to gather up all the enclave power armor. I'm going to do it anyways and sell the things for a million billion caps.
Ultimately that's just a number getting bigger.
This aspect kinda works with the Settlement building. You can buy these shipment vouchers for screws and adhesive and such. I say it "kinda" works since you end up having more money then everyone else put together in the world and the settlers are going to look a bit silly wearing combat armor all the time.

The Settlement building would work if the Settlers weren't such lifeless automatons. If the Settlers where characters i might grow to like and possibly want to protect i'd be playing some more.

Also if the main story wasn't such a clusterfuck i'd play some more.

I'd build settlements in the "Witcher" world. There are characters that i like and there are things i'd want to protect them from.