84% of American MLBers come from the first ten rounds of the draft. Slot money for the last pick in the tenth round this year was 142K before taxes. I’m guessing MLB doesn’t believe they are short changing the real prospects. MLB probably feels if the longshots (after tenth round) want to give it a shot great. A few will make it. Otherwise, there are other players willing to be teammates of the prospects to take their long shot opportunity.
Where MLB has gone wrong is not increasing MiLB wages with inflation over the past twenty-five years.