What should be noted up front is that the win differential (19 wins) between the Phillies and Astros is the second-highest in baseball history for World Series opponents, exceeded only by differential in the 1906 World Series between cross-town Chicago rivals, the Cubs and the White Sox. That resulted in the first great upset in World Series history, with the "Hitless Wonders" from the South Side winning in six.
But as the chart also shows us (reading upward here, from the green section into the two shades of yellow) there wasn't another such upset where the "David" team knocked off Goliath for nearly fifty years, when the New York Giants engineered their fabled sweep of the 111-win Cleveland Indians. Things were just kind of orthodox back in the old days, ya know?
Interestingly, though, the rate of these "win differential mismatches" has not changed much in the pre- and post-expansion eras. These things seem to be pretty random, and show a tendency to cluster (three in a row from 1938-40, five in a row from 1984-88, three out of five from 2005-09).
Since expansion, however, the outcomes of these contests have become much more random. After the 12-2 run of the team with the big regular season advantage essentially trampling out the vintage of their lesser-win opponent, it's all even-steven in the years leading up to now. The other hallmark indicator of such matchups--short series of 4 or 5 games--has faded a bit, as evidenced by the seven-game "rope-a-dope" win engineered by the Washington Nationals against those cheatin', trash-can bangin' Astros in 2019 (a World Series that really seems like a lifetime ago).
So--what to expect from this matchup? Well, aside from a lot of strikeouts, we did manage to tease one small-sample indicator from the pile of data. In matchups where the win differential of the teams is at the high end (16 games or more), the results strongly favor the team with the greater number of regular-season wins. In those six World Series, the "Goliath" team has a 5-1 record against the "Davids."
The Phillies have had a great little run, but they were aided by a seeding system that (as we noted previously) gives too much opportunity to the wild card teams and that possibly penalizes the best teams by keeping them off the field to "go flat" (as happened to the #1 and #2 seeds in the NL this year, the Dodgers and Braves, both eliminated in division series upsets). The Phillies didn't have to face the best team in baseball to make it to the World Series, but they will get a reasonable facsimile in the Astros, who are probably hungry to toss off some of the tarnish they've been wearing since the "trash can scandals" created the latest absurd overreaction from the "embedded media" (a force that just might be as much of a threat against democracy as the "trashy" forces unleashed against the government in 2017, and who, unlike the Astros, are still banging their trash cans as loudly as possible).
The average length of the World Series with a 16+ win differential between opponents is just under five games. So, if things stay with the realm of that dynamic, the most likely outcome is a win for the Astros in five games. And this is a year where, in so many ways, it would be as comforting as it would be useful to have a "reasonable outcome," despite the "allure of the other."