M&G Diner on 125th Street also lasted about the same amount of time. Fried Chicken platters were just over $10 a plate at M&G and now fancier restaurants uptown are charging $27 dollars. There seems to be room for something in between so why has that not happened?
Surprisingly there are a few places with diner type of food and prices for $6 -$14 dollars for a meal. Sylvia's and Amy Ruth all have platters at diner price points but are probably viewed as tourist attractions by many or unhealthy because of the southern food angle. A breakfast of sausage and two eggs is $6.50 at Sylvia's but most folks probably do not think to go to the notable tourist attraction for a regular meal. The interior also tries to be a bit too formal for a regular visit. Basically it all comes down to packaging. Diner food is definitely not healthy but more for comfort and an approachable environment. This comfort appeal trumps all health concerns and people generally go to them regularly because they feel more accessible in a day to day fashion.
Since some eateries uptown already have these diner price points, then why the lack of diners? It might be the case that these moderately priced business have long term leases and deep roots in the community that help them keep monthly rents low. New businesses have considerably higher rents and would have to charge more because of that fact. To make the monthly overhead, newer establishments are now heavily dependent on liquor licenses. Another point to note is that classic diners are also often multi-generational with family members working the business to help with the monthly upkeep.
So if any large families out there with restaurant experience wants to open a diner, than Harlem is ready. Just have a connection with the landlord or own your building to insure prices stay reasonable. Also have a casual, somewhat retro interior preferably with a classic service bar and stools in the layout. It does not have to be as intricately planned as Harlem Shake and can be on the smaller side also. Just get the decent food at a fair price down and folks will come.