Re: Prime Spock's last line?
I actually thought it was a reference to ST4.
In that film, McCoy insulted him by telling Kirk: "I don't know if you got the whole picture but he's not exactly working on all thrusters."
"Savor the fruit of life, my young friends. It has a sweet taste when it's fresh from the vine. But don't live too long... The taste turns bitter... after a time."