The difference between a docking computer and the suggested is that the docking computer uses an internal slot. This is more substantial of a choice than simply 'opt in/opt out', so it can offer more substantial of a gameplay benefit. The difference between the docking computer and external camera view is that the former can have some practical purpose and speed up docking for you (or allow you to go to the loo)
Are you just ignoring the context of the response? The quotes are there for a reason.
No, the current external view isn't really useful at all as far as gaining an advantage is concerned. However, it'd be foolish to dismiss any potential PvP advantages (context of the quoted) just because it's available to everyone. Just because it's available to everyone doesn't mean it's going to affect everyone the same way.
Opting-out applies to many features of Elite, docking computer is one of the examples. It being a module doesn't change players' option to opt out in any way. Any ship can have it, it costs nothing (because 4k or 5k credits or whatever it costs, is nothing). You have to sacrifice one internal compartment, which doesn't change the basic functionality of the ship (you can still trade for example and if you're short on compartments to fit everything you want inside your ship, no ship in the game has enough internal compartments to allow you for carrying every available module type anyway). The difference between the docking computer and external camera view is that the former can have some practical purpose and speed up docking for you (or allow you to go to the loo). Opting out does also allow players not to use features which break their immersion, but I see no reason why a person who's a bit less concerned about it, shouldn't be able to use such features.
External view doesn't offer any real gameplay benefit or advantage. Unless it's implemented in a way that does allow you for retaining full control of the ship. It is currently not implemented in this way and it is also not a solution the OP suggests.
That I can look at my ship from the outside? Wow, cool. And that's it. And I can do this whilst outfitting as well, so not much of an excitement when it comes to using external view camera. Novelty wears off quickly. Does it offer me any benefit in combat? Absolutely not. Firstly, when I'm switching to external view, the opponent is doing their thing (i.e. is shooting at me) and within that second of two it takes, they have already changed their position. And I don't even know where they are, until they decide to parade themselves before my eyes (i.e. camera is pointing at a right place at a right time). Then I will see them for a second and external view camera is not fast enough to allow you prolonged tracking of fast moving enemy. But hey, I get the significant advantage of seeing their bullets or lasers hitting the hull of my ship. If I was able to move the external view camera quicker, I would be able to track their movement, yes. But the second I switch back to the cockpit view, they are already somewhere else, so it makes no difference I saw them a moment ago. I can admire their paint job and decide it's cool (or not). End of advantage
I don't use the external view, switched to it probably 3 times to take a screenshot. I have the option of knowing where the opponents are just looking at the radar. Much quicker and much more effective. I think that radar gives me an unfair advantage, Frontier should remove it whatsoever then. As a matter of fact, if you're using turreted weapons, you don't really have much of a reason to even raise your eyes above the dashboard of your ship. So here's the extreme advantage of being able to look at the surroundings whilst in combat. For somebody playing with VR perhaps the canopy design would matter, for everybody else it only matters where your opponent is and how to get them in your crosshairs. Actually, let's ban the VR users, they are able to look around too quickly, thus getting an unfair advantage over players without VR kit.
OP doesn't suggest any truly revolutionary changes to the external view camera. Yes, probably it would be easier to follow the opponent's movements, but so what if you can't shoot at them? The moment you switch back to cockpit view to shoot at them, they are already elsewhere and you still have to use your dashboard / canopy field of view to locate them.
What they suggest would make it easier / more natural to use for purposes like:
1. Looking how pretty your ship is when in space or on the landing pad. Mine is a real beauty, no other ship ingame gets even close to looking that sexy.
2. Being able to take an interesting screenshot a bit quicker. Can't see how someone having a nice wallpaper for their computer puts gameplay experience of other players at risk. Perhaps other players would feel more miserable without that particular wallpaper and this affects their ingame performance, I don't know. It's the matter for their therapist and none of my business.
3. See your surroundings when somewhere in space, for example to evaluate your progress through the planetary ring whilst mining. Since that would be available to every miner out there equally, I doubt one person would blast the rocks any quicker than any other person.
4. Get a better sense of directions. Useful for new players on their first flights.
The change suggested would make the external view camera easier to use, but for activities that have nothing to do with combat (because of the reasons mentioned above). It is usable now, for sure, but making it more intuitive would be a huge help for the new players in their process of learning the game. I think it's a good thing, not hurting anyone in any way.
Personally I have no use for external view camera, in current form or with suggested improvements. I don't have to actually see the objects around to have a sense of their location, what I see through the crappiest canopy in front of me is good enough. But I can respect the fact that for some people it would make the learning curve less steep. I had the opportunity to observe one player yesterday struggling on his first day playing Elite to find his way in space. Had there be an option for him to switch to external view and have a quick look around, that experience would be much less daunting for him. So especially in the interest of new players I would wholeheartedly support suggested changes to the external camera view functionality.