Say you arrive to your clan's war a little bit late. Just type /score, and it will display the current score.

What do you think?

The leaders of clans open up a notepad or grab a piece of paper and write it down themselves.

~Not Supported

...nobody was keeping score?

It's for convenience. You don't have to ask everyone what the score is, you just type /score and it pops up.

It's nothing gamechanging, it's just that if I show up late to a war, I'd like to know the score immediately.

Alternatively, it could just give you the score when you join the room.

Always someone is counting score and telling it after every time.
Not supported.

It pops up after every match. No need to do this, unless of course, you don't pay attention. Just extra work that isn't really needed. If you showed up late, just ask others. Blame is on you.