MLB has parity only in the sense that the current playoff system of 12 teams making the playoffs produces somewhat random results in terms of championships. The Yankees have qualified for the postseason in 11 of the last 15 seasons. And here are the Dodgers recent win totals excluding the Covid year: 98, 100, 111, 106, 106, 92, 104, and four more seasons in the 90s. The big market teams have a decent chance every year to make the World Series. Even well run small market teams struggle to make the playoffs on a consistent basis, and when they do, they have an uphill road to the World Series. The Brewers have qualified in six of the last seven seasons but have not played in the WS those years.