Because dealers aren't stupid: Manual cars are very, very hard to sell these days.
Think about this: Two years ago, four percent of all vehicles sold in the U.S. were manuals. Today, that number has likely dropped to below three percent.
Let's assume that on a sports car like the 718, the manual 'take rate' is 20 percent. Why would you order a buttload of manuals for your lot that will be five times as difficult to sell as a PDK car? Taken further: With allocations so precious, why would you waste more than one or two a year on a car that will be five times as hard to sell as a PDK car?
From a dealer's perspective, stocking manual cars makes little sense. In 2018, if you really want a manual, order it. At least Porsche allows for this -- some never did before killing manuals entirely. (I'm looking at you, Audi.)
