The Old Mixer wrote:
^Just a guess, but possibly it has something to do with the fact that most consider "City" to be one of TOS's best.
Exactly so. "Yesterday's Enterprise" probably would not exist if not for earlier shows like "City" and certainly doesn't come anywhere close to the quality of the TOS episode.
"Yesterday's Enterprise" is a great TNG episode. It's good "Star Trek." It is nowhere near one of the best things ever done for television; there's better stuff being produced on a weekly basis in many genres (not just or necessarily sf) right now.