He’s a lightning rod for the playoff failures even though he generally performed well. The where’s my ring comment did not work out. And they would not have won four division titles without him. No Soto back then. Letting him go allowed them to sign Corbin which helped win a title. So there is that.
Circling back to Zim -- Zim has the satisfaction of playing his entire career with the same team and helping his team win a World Series. Even though Harper is a future HOFer he may never win a World Series and will never get the satisfaction of being associated with a single team. Furthermore, after he retires he'll leave town and head West faster than you can say "Three Hundred and Thirty Million".