C’mon, indeed. The questioner didn’t ask for the the NY Times review, he/she asked YOUR opinion.
If someone asks you for for your opinion on, say, Sam’s Grocery Store, and you answer to the effect that, “It’s OK but his produce isn’t often as fresh as it might be” that is 1) certainly l’toeles. and 2)unless you know Sam personally and have an issue with him, your only reason for commenting is to give good advice, not to stick it to Sam. That’s purity of purpose.
Note. If, in the example cited above, you had answered “…but the produce isn’t as fresh as Joe’s grocery.” that might have been a problem. Guarding your tongue doesn’t mean that you cannot be honest and objective. It means choosing your words carefully so no one can read into your words anything but what you intended and one recognize his or her motivations and act accordingly.