The difference, of course, is that basketball is a fast-paced, high-scoring game, and the entertainment value suffers mightily when it is slowed down. Soccer is about deliberately building to a scoring opportunity, so forcibly speeding up the game would simply ruin the structure. Obviously, "turtling" can be a bit of a problem as a result, but it's not hard for a team to sacrifice some defensive structure to press for a turnover.