Halo 5 Offline Games

I don’t know if there is already a Topic on this, if there is point me to it, and I will put my thoughts there.

So, Halo 5 seems to only be on servers. If they are down you can’t play the game at all. Why is the entire game on a server? What if my internet is out, and I wanna Forge or whatever. (I haven’t tried playing campaign without internet so I don’t know if that is an option when the servers are down.)

Halo 5 is the 2nd game I know of that is on servers. Destiny is on one, and if i am wrong, you can’t do anything offline. Why doesn’t Halo 5 have offline/private games. I remember on Reach. If the servers were down people played Custom Games, well we can’t do that anymore. The only thing in Halo that needs to be on servers is Matchmaking. Not Customs, or Forge.

Why was everything on Halo 5 put on servers?

Tinfoil hat explanation: Microsoft pushed 343 to require that the majority of H5 requires an Xbox Live Subscription.
Pessimistic explanation: Multiplayer and Campaign are the only modes available for play. Since Multiplayer needs online, and that’s where the majority of the game is, the skewed perception of needing an internet connection is visible. Forge is more of a tool, than a gamemode, since it’s purpose is to make maps to play multiplayer on. There’s also no other kind of offline content in the game (such as splitscreen, LAN or Traditional Firefight)