Sure, I agree there's no need for online-anything for these games. But it's not entirely implausible that Bethesda really meant for this to be optional because they thought it makes sense for whatever reasons. It probably makes sense for Bethesda, and if it's optional, even I would probably not mind it (although I would probably think it's fairly pointless). Anyway, this whole thing seems like a mess that could (and should) easily have been avoided.
But how could that be possible, even though it is someone else handling the project, Beth would still have to give a final say, a final overlook, before it is ready for launch, and we know they cannot do this completely blind, without at least some form of input from their end and a final resulting acceptance, that the games were in a state to launch. They must have known what they were doing when they gave their final word and greenlit release schedule. They had to have known what was going on with a network requirement, that feeds directly into a service network, which they own and operate.
Think of it this way, imagine you're running two offices, totally deperate from one another, but you still oversee office B from office A. Office B creates a project that requires the use and operation of the network service that office A owns and runs independently, but still requires the permission and input from office A, before anything can begin, let alone finish. If office A is informed, they allow the usage of their network and allow office B to begin their project, to make use of the network service provided by office A. Office B then finishes the project, and office A can then give the go ahead and maintain their network service, while overseeing how it is used by office B.
You must see that when someone operates a service like Origin, Steam, or any other client based network service, that the owners have to know exactly how it is implemented and when it is to be used. You don't just hand over network service usage blindly, and on a whim, without knowing what it will be used for. This is why I truly believe that it wasn't a blunder, and that it was never really meant to be optional, because why make it optional, when it was never even meant to be added for 3 games, 3 of which never needed such an ultra specific network service like Beth.net. They could have easily done what Nintendo does with Minecraft, in which you can just play with fellow ninty users. At least MS allowed it to be optional, to switch between XBL network service usage, or Ninty's own network service, but in this case, we wouldn't get a choice, as it would be using their network service, or not buying the game at all.
I could look at it in a myriad of ways they could have gone about this, but the reality is that those games didn't have it back then, why should they now?. If it's extra goodies for fans, then why not straight up add them directly into the games themselves, so they wouldn't require you to add to their total users using beth's client service user stats?. You can add goodies to a game without having to register to a specific network, we've seen it play out like that for years. It just doesn't make sense that they made a mistake, or for it to be optional, when it really wouldn't serve a higher purpose to being added in the first place.
DOOM 1-2 are really ancient games, and they could easily run on the big 3's own independent networks, without having to sign up to beth's network service, and we know this, because before cross-platform additions, the big 3 managed their own network services themselves, and still do.
I said it in another post before, but I do have a Beth account, yet I feel there is zero attachment to it, and thus I strongly feel like I'd have not much use for it. If they made it as important to me as say Steam or GoG's registrations, then I'd likely see them proving more useful and valuable to be if they presented something of value, that would entice me to use their service. So far there is nothing, and even what they currently have, I'd actually have to pay money towards it, which is the complete opposite of giving me value.