We had the Pandas for 20ish years, per the long-term agreement. San Diego Zoo was able to successfully breed many Pandas in that time, and had an integral role in breeding enough Pandas to get them moved from "endangered" species to "vulnerable."
I'm definitely bummed to see them go, but over the last two decades I've spent a LOT of time watching those goofballs.
Also, given how amazing the latest 'updates' to The Zoo have been, I have every confidence that if the Zoo replaces the Panda exhibit (I hear they're going to at least keep some offices and research center to shift into a different phase of working to preserve pandas) it will be w/something awesome!
Kinda sad, but I think the city, zoo, China, and the species have all benefited likely more than anyone imagined