Of course the real-world reason is that it’s cheaper to shake the camera and set off a firecracker than to build a scale model just to paint a burn scar on the side.
But my thoughts were always that the in-universe reason had to do with the modular nature of federation starships.
In almost every episode, someone on a starship either suggests rerouting something, shunting power from one thing through another, bypassing something, compensating for one power source with another etc.
It seems that in space, being able to re-configure everything at a moment’s notice is important, and to be able to do that, you need easy, fast and direct, access to everything, therefore it needs to be immediately accessible, ergo high voltage power directly behind the controls.
The lack of seatbelts goes right along with it. If a console blows up in someone’s face, the next guy over needs to be able to quickly move down and take over. Don’t need to have to be fighting with seatbelts when nobody is steering the ship.
I don’t know why they don’t have safety glasses however…
In an episode of DS9 I heard some of the characters mention that they not only have deflector shields, but also “structural reinforcement shields.” So whatever science-fictiony force field is used to protect them from phasers and micrometeorites is also coursing through the skeletal structure of the ship.
When I heard this it immediately clicked in my mind: whenever the ship is hit with phaser fire the explosions happening inside are recoil from these internal shields. Perhaps the catastrophic damage prevented by structural reinforcement shields outweighs the localized damage of potentially fatal recoil.
That is my favorite explanation, anyway.
(This assumes all ships have structural reinforcement shields, and not just the Defiant.)
Clearly if the architects had seen [any] [sci-fi] [ever] they would have come up with the idea to shunt that excess energy into ad-hoc shields for poor Ensign Redshirt.
Okay, I didn’t expect all of the examples to be from Stargate. But they certainly like that trope.