Carl5872
Prince
What you are missing is that there is a limited number of scientist specialists and that you are likely to hit that cap with or without that 2 extra food. Thus, the extra science tends to be better.
Even so, I think Id rather have a different specialist, and I know this is subjective, but say if youre Korea, you would probably trade 2 science for any specialist. Or even as any random leader I would trade the 2 science for an engineer slot.