Please show us if they are below level 80 by putting their level next to their name. The low levels usually rally the enemy on small scale fights because they are so easy to kill. If they are low level they do not belong in WvW. They are a burden! And certainly I do not want to invest my time in fights involving them!
I don't know why their level is kept secret, the only way to know what level they are is if you send them a team invite. That is a very tedious way to check for every single player that is around is worthy of your time.
And lets be real, it is very annoying when you fight 4 vs 2 and you manage to down 1 of them but your teammate who you did not know was a lower level died with a single attack and rally the enemy.