Combine vanilla wafer crumbs, granulated sugar, salt, and melted butter in a bowl and stir to combine.
Press the vanilla wafer crumb mixture evenly onto the bottom and sides of a springform or cheesecake pan lined with parchment paper.
Chill the crust for 30 minutes until firm.
Beat room temperature cream cheese with a mixer until smooth.
Add pistachio pudding mix, vanilla extract, pistachio extract, and powdered sugar. Mix on low until well combined, scraping bowl sides.
Pour in heavy cream and whip on medium-high speed until filling is light, fluffy, and smooth.
Spoon filling into chilled crust and smooth the top with an offset spatula.
Chill the cheesecake for at least 6 hours or overnight.
For whipped cream, combine heavy cream, powdered sugar, and vanilla extract in a bowl and whip until stiff peaks form.
Spread or pipe whipped cream on the chilled cheesecake and sprinkle with chopped pistachios, if desired.