Maybe I can phrase my thoughts better. There are two possible scenarios for a locked region:
a) There is nothing in the locked region. Except from them being in the way a little for navigation there is nothing to be gained from unlocking them. Making navigation around barnard's loop easier is a valid reason though. I doubt having a locked reason on the other side of Sag A* has any meaningful impact on player navigation as a whole.
b) There is something in there, and players want to see it. This is the motivation I suspect behind the "unlock all locked reasons" request. But if there is something, it is a reasonable assumption that it is the same in live as it is in legacy, and that it is not meant for us to see at this time for whatever reason.
I think the motivation behind the unlock request is b), as in "come on, let's see what you are hiding there, you are not developing it further anyway". But what is hidden there is either not meant for us to see (development) or meant for us to see at some later date in live. So unlocking it in legacy will spoil it for everyone else, and what is in there in legacy is further developed in live.
Does that train of thought make sense?