The announcers keep referencing stats going back to the 1920s. It's hard to imagine that anything was similar enough for a team's record in the 20s to be relevant to how the game is played today.
Does it break rules to ask a general question about major changes in professional sports and have kind of a sports open session post–game 7? There didn't seem to be a sports section in the FAQ.
Increased number of teams
Broader geographical distribution of teams
Refinement of rules
Technological improvements to equipment
Increased size/speed/strength/skill of players
Increased salaries allowing players to devote full time to the game
Broader media coverage (radio, television)
In baseball specifically, while the fundamental rules have not changed much, the composition of the ball has evolved over time from a more loosely wrapped, less dense ball in the late 19th century through the 1920s, and a more tightly wrapped, more dense ball thereafter. The game was originally played by the fielders without gloves. Later the fielders of both teams shared gloves and just left them at their position. There are now highly specialized gloves for each position (catcher, first base, third base, middle infield, outfield).
The advancement of radar technology has arguably put more emphasis on velocity from pitchers. Curveballs used to be illegal because they deceived the hitter. Originally there was really no ball-strike count. The umpire would "warn" the pitcher he was throwing bad pitches or the hitter that he was taking good pitches. The goal was to throw a pitch the batter could hit. Later, emphasis was put on breaking pitches. Today breaking pitches can be quantified by various radar measures (spin rate, movement, etc).
In the early 19th century speed and contact hitting were emphasized, with bunts and stolen bases being important aspects. Later in the 1920s, home runs became much more common. By the 1960s pitchers had begun to dominate hitters and the height of the pitcher's mound was lowered from 12 inches to 10 inches, resulting in a return to prominence for hitters that lasted until the 2000s, when pitchers with 100mph fastballs and effective breaking balls became more common, as well as specialized pitchers and advanced split stats improving strategy against specific hitters.
In a nutshell, the core game has not changed much, but many of the details and nuances are quite different today. If you watch old newsreel footage of baseball from the early 20th century, you know you're watching baseball. If you watch a game from the 60s it doesn't look or play that differently. I would say the modern game is more highly refined and specialized.