The Houston Astros haven't yet lost a game in the playoffs, so it's no surprise that they're sizable favorites to win the World Series over the Philadelphia Phillies. One big reason, though, is how loaded they are with top-shelf, battle-tested talent, as evidenced by the first tier of this ranking of players in the World Series.
This isn't a straight ranking of regular season WAR -- it's about how these players will be used in this series. I'm ranking these players based on how good they are right now, using the role that they will likely play this week as a tiebreaker. For instance, I slightly prefer Aaron Nola to Zack Wheeler (as I did before the playoffs started, when my sources indicated a toss-up), and since Nola is starting Game 1 and thus could appear three times, he gets the slight nod. (Due to my tie-breaker rule, Wheeler would have slid ahead if he were the Game 1 starter.) Nick Castellanos has had a disastrous 2022 on all fronts but will probably start every game for Philly, so he'll slide ahead of some players who had better seasons but will only be used as defensive replacements.
The toughest part of this (and something that will split fans and analysts) is balancing season-long performance with how a player is performing in the past few weeks. The analytical types will say the hot hand should carry little weight; fans will say "but this guy is red hot!" The answer is somewhere between the two, but, to be clear, it's hardly a science.