If you have cracked FTL I'm pretty sure quantum entanglement is a drop in the bucket...considering we are already beginning to harness quantum entanglement and yet have little to no ideas about FTL.
Possibly, although it's not a good idea to compare current research against the research that may or may not have been done in the ED universe. It's possible they did research but found it wanting (QE, if my Mass Effect history is on par, enables instantaneous communication anyway in space between two points, that's it - for an interstellar civilization) and ultimately dropped it, who knows?
I see no reason system-wide/instance-wide chat is immersion breaking. Especially considering a chat that would be accessed how Lustan so kindly illustrated
I see no real issue with system/instance chat either, or even galactic .. my issue is the instantaneousness of it that would be immersion breaking.
"Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space."
As such, an instantaneous chat system that has no basis in lore is immersion breaking; not to mention one of the main things which gives ED that sense of scale is the fact that you can't just open up a chat window in game and start talking to a plethora of people. Being in deep space, tens of thousands of kylies from home and being unable to communicate with people really brings it home that you are alone out there. Instant chat to your friends is bad enough as it is. Of course, this is my personal opinion and is no way rooted in fact; but I suspect a great many people feel the same.
As far as I am concerned, it has to a) fit into lore, and b) have an element of realism to it; by realistism I mean, whilst in human space, your chats are delayed - that delay gets shortened the closer you are to a communications relay (such as a station), at a station for example, there could be almost no lag time; it's perceptible but is minute. However, the farther you get from human space the longer the delay until ultimately, you can't global chat with anyone (this should be implemented across friend chat too).
Side-note: What people do outside of the game is their own business, if they want to TS they can. That's no business of the game.
Plus even if we cut out quantum entanglement, there are still communication buoys and relays...heck there could even be missions tied to it when wanting to expand chat and such into further reaching systems. I know as a n00b I would've enjoyed some kind of way to chat with players and get help in game.
If we cut out quantum entanglement and use modern radio waves (for example) to send communications, it would still take 4 years for a signal to get from Earth to our nearest neighbour as radio signals are a form of electromagnetic radiation and thus move at the speed of light. Even if they were to shorten that down to say, a few minutes, it would STILL take a long time for signals to get around human space.
When I was a noob, I was grateful for the lack of hand holding; I am sick to death of games holding my hand. I adore ED's style of dropping you into the deep end and saying "have it, Cmdr." Plus the lack chat actually helped my immersion by giving off the sensation that space is big - doing that in a game isn't very easy to do, and, imho, almost impossible when you can just be like "meh, approaching the eastern spiral arm, 75,000ly from Sol... so what you guys up to?" to a thousand players.
The definition of immersion breaking to me is how they have a link to a youtube video in the main menu showing you how to dock/fight etc.
Why are you trying to get immersion when in the main menu? That makes no sense.
Plus...get over it. I love immersion as much if not more than the next guy, but this is still a game, and you will never forget that (well...maybe with VR)
Of course I (and others) will never forget that, but we don't want it thrown in our faces every second through a global chat system which, quite frankly, was left out of the game for good reason (the devs didn't want chat spam which is inevitably what will happen).
So how about no, I will not get over it; I am entitled to enjoy my immersion, and I am equally entitled to express my displeasure at anything that I feel breaks that immersion. Just because YOU want something, doesn't mean other people must just roll over and take it.