MLB peaked in the 1960-1991, like NFL of last 20 years, could have 2 small market teams in the world series and get like 40-60 millions for the WS(1980 Phillies-Royals Game 6 was watched by 56 million of americans,Royals-Cardinals game 7 1985, 45 millions, and Game 7 of Minnesota-Atlanta was watched by 50 millions of americains) was hurt by the strike but got back after nicely, but lost ground to the NFL for good after 1995.
NFL dominated right after COMPLETELY. They are at the level MLB was from 1960-1991 right now.
I know NBA from 1984-1998, basically the Magic/bird/Jordan/pippen/Rodman era had a strong surge of popularity and revelance, but the 1998-99 lockout and the early to mid 2000s nba had a negative effect to them. NHL enjoyed a surge of popularity in the early 1990s, but the lockout of 1994-1995 and the defensive system used by many teams, alongside with expansion to less tranditional markets, made the talent in the league paper thin and teams could win purely on system and less on overall talent. Casual fans new to the game were turned off and the media ignored the sport.