In a mixing bowl, combine vanilla wafer crumbs, granulated sugar, and a pinch of salt. Pour in melted unsalted butter and mix until well combined. Press this mixture firmly into the bottom and slightly up the sides of a 9-inch springform pan, creating an even layer. Chill the crust in the refrigerator for 30 minutes to set.

In a large bowl, beat room-temperature cream cheese with an electric mixer until smooth and creamy. Gradually blend in the instant pistachio pudding mix, vanilla extract, pistachio extract, and powdered sugar until well incorporated. Gently fold in the heavy cream using a spatula until the mixture is light and fluffy.

Fill the chilled crust with the cheesecake filling. Use an offset spatula to spread the filling evenly, smoothing the top. Cover the pan and refrigerate for a minimum of 6 hours, ideally overnight.

Whip the heavy cream with powdered sugar and a splash of vanilla extract until stiff peaks form. Keep chilled until ready to serve.

Once the cheesecake has set, carefully remove it from the springform pan. Spread or pipe the whipped cream over the top and sprinkle with chopped pistachios. Slice and serve cold.