If your teammates actually shot at the enemy rather than facing them/not noticing them anyway and doing nothing they were already around at least median level of usefulness. Any form of communication or skill above what I would have expected from my nephew when he was 10 are bonuses!
Right, it was always stunning to me how many people log into these games and then don't participate. Some were probably bots, I suppose. In the games that have progression trees, I think you always gained some "XP" or whatever from games that your team won, so having a bot simply log in and then do nothing would, over time, accrue some in-game currency.
Also, the games themselves are usually poor at instructing new players, so once the game has been running for a while, new players are dropped in with the sharks.
Company of Heroes had a system for attempting to match players by skill, but the other games I played didn't even bother.
CoH usually had 1-3 players on each side, while something like
World of Tanks has 15 on a side, and 30 players by skill would probably be really difficult, and/or take a long time. The upside was that you could get a game of
World of Tanks in less than a minute, even if it meant half of the 30 players weren't really meaningful participants. I think
WoT introduced a revised and expanded tutorial for new players after I quit, so I never got to see how well it did. I was fortunate enough to get into the game early, before players had time to become extremely good. It must be hell for novice players now.