That's certainly something some folks may find issue with.
The root of it is the video game paradigm of the health bar.
We'll have a health bar in Fallout 4, and so will all the enemies.
To resolve this, however, a new standard in damage calculation without the health bar would need to implemented.
Like the real world, a homeless drug addict with a box cutter can cut your throat and kill you as quickly as a trained military sniper with military equipment.
Implemented as such in a game world, there could be a bit of scaling, but, across all levels, a head shot, a cut throat, a severed limb, a through and through torso wound should have similar result.
This would require getting rid of the health bar, and implementing a triage indication on location damage from light, medium, severe, and imminently mortal, or immediately mortal. It would also require quite a bit more sophistication with the armor system, such that higher level enemies, while they could plausibly be killed with one shot, might take more than that due the kind of armor they're wearing, where they're hit, and what they've been hit with.
I'm sure the technology is available to implement more realistic attendance to damage and how armor could mitigate it, but, on the other hand, we've a video game standard in place, and this is a video game, and if some of the basemant dwellers are ready to rage quit over a voiced protagonist, or skills getting absorbed by perks, imagine the squeals and cries of offense if the health bar were eliminated in favor for a system that you, or anyone could get killed with one shot and damage calculation was significantly more flat and realistic.
It'd probably break the internet.
On the other hand, it would no longer matter what level any character or enemy was. All enemies across all levels would then be potentially just as deadly as at the very start of the game, and the player character would never turn into something like a god in power. All enemies would need to be dealt with with caution.