The spacesuit skeletons are just robots with dead people stuck inside them. I don’t see what’s so hard to believe about that.
If power armor can't walk around on its own then I don't buy it that a rubber suit with some electronic components inside of it can walk on its own.
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I should clarify, when the people in the suits died they would go through the decomposition process which means that fluid would start draining. I don't really buy it that the inside of the suit is completely sealed against all those potential fluids. Or were the suits stuffed with skeletons after the fact?
Anyway, if the suits have been around for 200+ years moseying about then we get into the same problem I got with pretty much any robot that's just wandering the wastes. 200 years is a very long time. Too long. If they made more suits or made them post war then again I just don't buy it that they have massive stockpiles of resources that they can go through or that they can just recycle things over and over again.
There is a way you can make these suits work. I just don't think it is in Fallout, especially if they're 2 centuries old.
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Now I got an idea for how to make them work actually. See the suits themselves are a new technology that they were doing just prewar for the intention of automized power armor but needed a prototype suit first so that's where these ones come in. The tech is basically synthetic muscle and tendons and a very strong radio signal that goes to a ZAX super computer. Pre-war these scientists, assistants and engineers were informed to use these suits when doing normal tasks. The suits would record the data and send it to the ZAX super computer to analyze and store programmed repeated patterns. When the nukes dropped and things got hairy those who survived used the suits as they provided excellent radiation protection and kept trying to appease the Think Tank.
Due to the harshness of post apocalyptic life as well as their new found fascination with lobotomy it meant that they had to engage in a lot more combat. So while they tried their best to maintain various technology to make sure it would work they also had to fight off hostiles. Creating a defensive protocol. When these people died the suits got shelved for a while but as things started to fall apart whoever was in charge of this division, let's just say it's Zero, had to fully test the program again as they couldn't wander out and just fix things here and there.
But the suits would not work on their own because they don't have the rigid component inside that were necessary for the suit to stand up, imagine yourself without bones, you'd just flop to the ground. So he stuffed the suits with the skeletons of his former employees and activated the program and sent them on their merry way. Whenever a suit is damaged and can no longer function the other suits would take it to Zero to fix it, eventually he got tired of having to do this so he would try and teach the suits to take care of it themselves in order to be selfreliant.
Now the reason for why they're hostile towards you is because, well, you're a lobotomite. They can just tell that you are and will shoot on sight as they've been programmed to do.
Now these suits are reliant on radio signals so they would only stick around areas that are near said signals, gameplay wise if you stepped outside these ranges the suits would just collapse and "die" or they would retreat and end combat sequence. If you kill a bunch of them it would trigger Zero to comment on it the next time you visit him where he asks you to please avoid killing them as every time you do they need to repair themselves and the stocks aren't endless, indicating that in fact resources are not limitless and it is a concern to the Think Tank.
I think this could've worked within the lore, it's not perfect but it would explain why they're still around, why they need skeletons inside of them, the fact that the skeletons were put there after the fact. How they can move around the way that they do (ZAX super computer doing the computing work). Why they attack you the player. As well as why certain things around Big Empty are still functioning after 200+ years; It's cause the Think Tank delegated the work to the suits to perform maintenance tasks and keep areas safe. Personally I would changed the suits designs to have variations where there would be these little patches of off colour, indicating that they've been repaired.
So I mean, I don't oppose the idea of it. It's the implementation that I don't like. What I just wrote is complete fanon and irrelevant to the actual lore in OWB.