NO, I don't want to know what has hurt baseball.

Because I ALREADY know. And it is
exactly what I've been talking about in this thread since the OP. It is the 1994 MLB player's strike, the spoiled brat attitudes of pampered, overpaid players, free agency, things like the Price drop (notice I don't call it a "trade"), overinflated ticket prices, parking prices, concession prices, and the whole anti-fan, greed freak management of it.
In 2014, 35 percent of fans call the NFL their favorite sport, followed by Major League Baseball (14 percent), college football (11 percent), auto racing (7 percent), the NBA (6 percent), the NHL (5 percent) and college basketball (3 percent).
In 1985, the first year the poll was taken, the NFL bested MLB by just one percentage point (24 to 23 percent), but since then interest in baseball has fallen while the NFL has experienced a huge rise in popularity.
Nine percent fewer fans call baseball their favorite sport over the 30-year span, the biggest drop of any sport. The polling numbers suggest that the sport hasn't been able to recover from a popularity standpoint from 1994, when a strike forced the cancellation of the World Series. And it has just continued sinking ever since, for the same basic reason > Greed freak baseball.
Harris Poll -- NFL still most popular; MLB 2nd - ESPN