Add to that the fact the game is made with fast travel in mind. At least I hope they don't have to fex-ex questing back and forth between the same areas over and over and think a player would be super excited to get to walk it the whole way with it already cleared. As you mention, you'll complete an objective, have to run back to effectively turn the quest in, and you'll be given another objective that may very well be at or near your previous one. Fallout 4 especially is designed fundamentally to use cities and settlements as home bases you return to often, and not being able to fast travel, and with a smaller inventory is counter to that design.
If they charge you resources to travel then it's not really making the game more engaging and complex. It's just creating a downtime penalty when you aren't actually playing the game. Some people are into that, some not, but either way I think it's lazy game design that often results less in you being more attentive to actions in the game but simply having resource bars and UIs you're playing against.
Every game ever is essentially a resource you're playing against. Even if it's not in the UI (Like Mario's one life) it's a resource you're playing against. Longer term strategies tend to illustrate the resources in the UI since the decision making is broader and has effects that happen over longer periods. There's nothing 'lazy' about resource management, it is all about how it is executed. Avoiding a failed state by managing resources, so you do not have to expend extra RL time, is nearly what every game, ever, is based off of (In the end it can all be divined down to that)...So I don't think it's not engaging and complex as a matter of fact, I just think that's your opinion--I personally don't find APM difficulty engaging or complex, yet most of the people in my guild jacked off over the fact that I could get gladiator or was decent in SC.
As for the super excited to walk part? Again, you're really underestimating how some people feel about ambiance and environments. Large swaths of people use mods in Skyrim to turn
offfast travel because they like the immersion of simply having things take more time, to make the world feel larger. They LIKE actually making choices and arranging quests based on how far something is (And they add all kinds of mods like Frostfall and needs mods to make those decisions have more impact than simply time spent.) For some people, the mere aspect of having to move through the environment in a way that provides a high fidelity is ALL that is needed to make something worthwhile. You're confusing what makes a great game, with what makes a great experience/world, they don't always match up (EQ was a terrible game, but an excellent world, WoW is the opposite I feel, very bland, chopped up world, GREAT game though)--some people would gladly forgo various aspects that would create a more aerobic game experience for the general experience of a world that requires time and feels like it has scope.
However, I think the vast majority of people who like survival fall somewhere in between. Where those two things are blended together. Survival is supposed to make those cities more than just quest start/stop points, they are supposed to be places where tension is relieved. If the game doesn't make you consistently feel tense while being in the environment? Then it's not doing a good job being a survival game IMO (but it might be doing fine being an experience/world). That's why I said above, resource driven movement, is an aspect that goes towards that--but it would have be done with a lot of caveats.
Why not make the actual areas the game is sending you to be what's meaningful? Why not make that quest marker where the content is? Remember, we have to run there initially, but why should the run back to the same area for the 4th time be what they focus on for challenge and engagement.
random encounter and don't carry water because it's as pointless as all the other just loot you're constantly loaded up with
If you have to run back to a cleared area 4 times, the game isn't doing a very good job of managing its content; that's an issue with making a survival game fun, sure, but it isn't the issue of why fast travel does not work with a survival game (At best its tangentially related, since it would illustrate the game isn't designed well for good survival aspects). In addition, I think we agree with a source of the problem,if not the solutions--the resources are all but meaningless, why should I care about the environment if it can do so little to hurt me (If I don't even have to care about water)? Running out into the wastes 4 times shouldn't
just be a chore, it should be avoided because its dangerous and difficult and taxes your
limitedresources. (If your game is essentially an ARPG loot fest, that's all null)
The whole design should make avoiding those 'extra' runs into the waste possible to a smart player, without the need for fast travel. In fact this should be the core of survival games, well planned expeditions, efficiently going places so you don't need to retread your steps, so you can spend those resources upgrading your character instead. If a player HAS to run to the same place 4 times, despite decent planning, the whole design is fucked before you even add the survival elements (Caveat being, of course, if the place respawns, or develops new resources). What you're describing simply bad, un-engaging encounter design, and layout, not why fast travel is 'needed' but rather why it's needed to correct THOSE issues in
thisgame. A decent survival game wouldn't have those (Which I think we both agree on). After all, survival is about making the environment have MORE of an impact on the player, in order to offer a meta game AND increase (As described above) the fidelity of the experience. Fast travel is the antithesis, it is literally a function meant to skip environmental interaction. It's like buying a car because you want to fly everywhere. It's fine in a game not meant to emphasize those aspects of a world (Like FO4 is obviously meant to be) but it's dogshit in a survival game.
Which is what you're saying, the game is designed poorly from the ground up, so adding the survival and environmental engagement aspects don't mean much. Nothing in my point contradicts that, though. The point is simple, with fast travel ANY survival mechanics you add are meaningless, because you'd always be able to simply warp from trouble (Even if you prevented it while sick/tired ect; you'd only bring just enough gear to alleviate those once, and warp out before your failed state). In order for the environment to have any impact at all, you either need to spend time in it, or it's effects need to be abstracted as if you did spend time in it (For those not overly concerned with the whole 'experience' thing). What you're saying is the things within the environment are also boring, and that's fair, but it's a very different argument. (That said, a good survival game should make this all work together. Different environments should challenge your resources in different ways; combined with mobs/quests and other things in that environment making it feel genuine and also adding to the taxing effect on your resource management).