Preheat oven to 375° and grease a large deep dish pie pan.
Make the filling. Add the cream cheese to the bowl of a stand mixer and using the paddle attachment, beat until smooth (about 1-2 minutes).
Add the canned pumpkin and maple syrup. Using the whisk attachment, whisk the mixture until there are no chunks of cream cheese remaining, pausing to scrape down the sides of the bowl if needs, about 2-3 minutes.
Add the eggs, 1 tbsp pumpkin pie spice, and vanilla extract and whisk again until the mixture is well combined. Set aside.
In a separate bowl, stir together the rolled oats, flour, brown sugar, pecans, 1 ½ tsp pumpkin pie spice, and salt until well combined. Add the melted butter and stir until the mixture is crumbly and well combined. Set aside.
Pour the pumpkin mixture into the greased pie dish, then top with the crumble topping mixture evenly. Bake in the preheated oven for 30-35 minutes, or until the top is golden brown. Allow to cool at room temperature for about 30 minutes, then serve with whipped cream and/or ice cream.