[wigl]

As someone who plays a lot of online multiplayer, there's a few issues. A lot of games do have skill based matchmaking systems (aka SBMM) in place.

Ideally, this would lead to people having a 50% win rate which is just unacceptable to some. Those people resort to smurfing or cheating to get their fix--they don't really want a fair and equal match. Just look to the Call of Duty community crying about SBMM. Those people want to farm clips and play with those worse than them--not people at or above their skill level.

Additionally, many multiplayer games at all but the highest skill levels have most matches determined by the side that plays the fewest number of mistakes. This is especially true of team based games. At most skill levels, both teams will be making many obvious (and less obvious) mistakes. This can frustrate some who believe that they're held back by their team and just need to play with higher ranked teammates. So people will boost or buy accounts or resort to cheating.