Whether or not there is an advantage to going first or second is moot. No one knows and any proof offered is just opinion. People stating there is or is not an advantage does not make it so, no matter how loudly people say it. The only people with proof are CG, and even then it doesn’t take into account individual players psychologies.
From personal experience as someone who had to change when they attacked in GAC for 3 months last year, because of a move to a different time zone, I was bouncing between K2/3 when I always attacked first, and then after 3 months of always attacking second I was, shock and horror, still on the border between K2/3. Since moving back for almost 2 months and always attacking first I am still on the border between K2/3. Any advantage is an illusion in players minds, not a fact.
Back to the actual point of hiding scores I’m a hard no. When I attack first I like being able to see when my oppo attacks me, and to watch as they smash through the defence I’ve left which is often only slightly tougher than a damp tissue. When I attack second I like to know when I can just give up and call it a day, or alternatively use it as a chance to try an off-meta counter against an unusual/unused team of theirs or of mine. Knowing a GAC battle is lost is one of the few times when I can try out squads in a ‘sandbox’ environment. For all those reasons and more keep it as it is. CG have enough trouble fixing actual bugs in the game without creating more ones (see the recent TB fleet missions debacle) so implementing hidden scores should be at the bottom of a priority list IMO.