I don't entirely concur. I don't think their specific ages are directly enough related to their arc to need to be clarified. I think you can pick up anyway that Spock is older chronologically but I don't think it's a specific detail that would have needed restored. Not at the expense of damaging the opening they had anyway. It always sounded to me like one of the moments that seemed 'needed' at the writing stage and filming stage but then when they got to editing realised it wasn't for the film to work.
But that always happens in the time and space between script and editing once filmed.
'If the Apocalypse starts, beep me!' - Buffy Summers
'The sky's the limit.....' Jean-Luc Picard, 'All Good Things'
courtesy of Saquist