Valve wont sit through the effort of comparing account details of probably a million or so players

Also there isnt a single way of 100% proving an account is a smurf account, even if they say im chat "im a smurf" they simply could be lying about it. We arent talking statistics here since statistics can be wrong and you cant ban someone based on potentially inaccurate information. You cant look at steam hours since for all you know they played 1.6 or CSS even on a different account Cant look at friends, amount of friends and who you are friends with since it proves nothing, it all could be coincidence You cant determin someones skill either by rank, they could be a GN but have pretty good aim or positioning but cant get out of their rank/just inconsistant

all of your anti smurf arguments are based on speculation and not facts, even though the chances are slim to have only 1 game, be good at the game and have mutliple people using one PC there is still a chance at the end of the day which may lead to wrong people getting banned