When player count is low it's impossible to kill players with a healer in the party since even focus from several players is not enough to break through heal. Players with a healer in party can run naked without defence buffs, yet can't be killed.
Newbies without a healer become the only killable players and first priority targets..
In the end newbies leave after an hour of gameplay because they are the only being focused.
It's not about newbies are low level / low equipment, not about elo balance. It's about newbies are first priority targets. This ruins mid / late game and makes newbies leave very fast.