In New Vegas DLC the courier gains control of a nuke and has the option to nuke somebody. In the main game he gains control of an orbital solar weapon. He also has control.of the Boomers and their bomber. Regardless of his choices, all the endings leave the door open for the courier, House, the Legion, the boomers, or an NCR faction to take out Shady Sands with any of those. For all we know the Courier was a vaultec operative.
Or was triple crossed.
And yes, in 2281, there were signs of internal problems within the NCR so an internal faction could have already be undercutting the republic. In fact, the conflict might have been started by the Shady Sands authorities.
The thing to remember is the canonical game endings are not guaranteed to actually stick. Or be the whole story. In the wasteland nobody trusts anybody and everybody lies. (That only adds to the fun.)
And that includes the mother of fire (who need not be dead--how'd she survive 220 years?) or the "kindler gentler" vault 4 survivors.
As to the airship, even if the Prydwen was destroyed, we could be looking at a replacement, the Prydwen A, and the east coast brotherhood could have returned to take Boston afterwards.
Bottom.line: everything can be canon and not-canon through events off-camera.
All we know for sure is:
- There is a brotherhood outpost in the commonwealth, and thus in the Capitol Wasteland
- The Enclave is still active somewhere in the west
- The Brotherhood has cold fusion and thus the means to recharge fusion cores
- New Vegas is dark at night. Whether it is dead or power-limited is TBD as is who, if anybody, is in charge.
- Vaultec is quietly active as a previously unknown faction. Not all Vaults are accounted for. Somewhere they have one or more establishments with nukes and advanced tech. (Maybe Zetan toys.) Note that Hank knows how to use power armor.
- Vaults 31,32, and 33 look to be a eugenic program to breed a better breed of managers. Note Lucy's intro in episode one, listing her skills: repair, speech, science, unarmed, small guns, etc. She might be naive but she is well trained, and cool under pressure; clearly intended for a managerial role.
Unknown: power structure in the Commonwealth and New Vegas
Fate of The Institute, Railroad, Synths, The Pitt, Scorched, Super mutants, and Zetans.
For all we know, Vaultec is tied to the Zetans.
Season 2 can't come fast enough.