[Fallout 76 forum?]

Considering all the negative things Bethesda pulled of with as well as the fact they COMPLETELY under delivered compared to their previous work, combined with the kind of business model they are practicing with this game, I wont support it. Fallout games are supposed to be great singleplayer experiences, not some half baked, poor man MMOs. ANY self respecting Fallout fan should stay the hell away from this game.

[Why the Bethesda RPGs don't allow fast-traveling from indoors?]

For an extreme example, when you fast travel out of the starting prison, without having finished the tutorial dungeon, over the course of which you also select your class and birth sign, i.e. define you major skills and what not, you won't be able to gain skill points or level up. I ran into it due to exiting the place right after race selection and cosmetic setup through a console command, and it took me half a day to figure out why this newest play of mine never increased its skills or was still level 1. Served me right for essentially breaking the game intentionally, even though I wasn't aware.

 

Now let's take some less extreme examples.

Say you stole something/killed someone and are locked into prison to serve your time, have your attributes damaged or the like. When you're able to just fast travel out of it, that'd be totally unimmersive.

Minor spoilers:

 

 

Being locked into the dream world or inside the painting, how would the quest be still finishable, if you just fast travel out and due to the quest being locked at its current stage can't even get back in?

 

 

There's actually quite some cases of quests where it's 1-way entrance, no way out, until you solved it. Being able to fast travel out of them would definitely break them, bar you from ever finishing them and get your rewards.

Your both examples are absolutely correct as it depends upon the case and situation