Baseball playoffs are the most illigitmate and inconsistant of the 3 major sports. It's simple logic.
Baseball plays a 162 game season and then there is the potential for 19 playoff games. That's equal to 11% of the season.
Football has 16 regular season games and then a maximum of 4 playoff games. That's 25% of the season.
Basketball has 82 regular season games and then a maximum of 28 playoff games. That's 34% of the season.
See the difference? You can't play a 162 game season and then expect the next 15 games or so to be an accurate representation of the best teams. There is a lot of luck involved.