Some bad luck and more importantly not enough XBH power after Soto and Hernandez.
I don't think the offense is far off from being enough to win the NL East. Small steps forward from Kieboom and Carter, a major league average middle infielder, and perhaps an extra corner OF bat that would be passable as a #5 or #6 hitter, and this offense is pretty good in my book.
My dear Yadiel looks to be a reverse platoon hitter, so it looks like an extra RBH in LF to help protect Soto would be a good add. I don't trust Escobar to repeat this performance, but they should definitely bring him back.