MLS any better as a league, and the owners realize it. The owners could set the minimum salary at $75,000, and what's that going to do? It's not going to bring in any additional talent that MLS doesn't currently get anyway, so it ends up being just a waste of money. The only way to increase the quality of the league is to focus on the overall salary cap, not the minimum. The league won't get substantially better until the players who are now making $80k-$120k are making more like $300k-$500k, because that's the point at which MLS will stop losing talented players to Europe and drawing more talented Euros and South Americans.

The minimum salary players are minimum talent players. Most of them are end-of-bench college kids living their dream playing pro soccer. MLS will get them whether they're paying $32k per year or $75k per year. Sure, some of them might turn it down or move on after a couple of years, but big whoop, they don't elevate the quality of the league anyway, and can be easily replaced. For a single 23-year old kid with no responsibilities, $32k isn't actually all that bad of a wage for playing soccer eight months out of the year.