In a medium bowl, mix gingersnap cookie crumbs, melted unsalted butter, and a pinch of kosher salt. Stir until the crumbs are fully coated and moistened. Transfer this mixture to a 9-inch pie plate, pressing it firmly into the bottom and up the sides. Freeze the crust for at least 30 minutes.

While the crust is chilling, beat softened cream cheese and powdered sugar in a large bowl until smooth and creamy, about 2 minutes. Add pure pumpkin puree, vanilla extract, and pumpkin pie spice. Mix until completely combined.

In a separate, chilled bowl, whip heavy whipping cream with an electric mixer on medium-high speed until stiff peaks form, about 3-5 minutes. Be careful not to over-whip.

Gently fold half of the whipped cream into the pumpkin mousse mixture, maintaining its airy texture. Then fold in the remaining whipped cream in two batches. Pour the pumpkin filling into the prepared gingersnap crust, smoothing the top. Cover with plastic wrap and refrigerate for at least 3 hours.

In a clean bowl, whip together heavy cream, powdered sugar, maple syrup, ground cinnamon, and vanilla extract until fluffy. Spread this topping over the chilled pie and sprinkle with a dash of ground cinnamon before serving.

Let the pie sit at room temperature for 20-30 minutes before slicing for easier serving.