Make the crust Combine graham cracker crumbs, sugar, and melted butter in a medium bowl. Mix until the crumbs look like wet sand. Press the mixture firmly into the bottom and slightly up the sides of a 9-inch pie plate. Use the bottom of a measuring cup to pack it evenly. Chill in the refrigerator while you prepare the filling.
Whip the cream Pour the cold heavy cream into a large mixing bowl. Beat with an electric mixer on medium-high speed until stiff peaks form, about 2–3 minutes. Set aside.
Prepare the cream cheese base In another large bowl, beat the softened cream cheese until completely smooth and free of lumps, about 1 minute. Add the powdered sugar and vanilla. Beat again until light and fluffy.
Fold in the whipped cream Gently fold the whipped cream into the cream cheese mixture with a spatula. Use broad, sweeping motions so you keep as much air as possible. The filling should look smooth and cloud-like.
Fill the crust Spoon the filling into the chilled crust. Smooth the top with an offset spatula or the back of a spoon. Cover and refrigerate for at least 3 hours, or until firm.
Make the strawberry topping Just before serving (or up to 2 hours ahead), place the strawberry jam and water in a small saucepan over low heat. Stir until the jam melts and becomes pourable, about 1–2 minutes. Remove from heat and let cool slightly. Toss the sliced strawberries with the glaze until evenly coated.
Top and serve Arrange the glazed strawberries over the chilled pie. Slice with a sharp knife wiped clean between cuts. Serve cold.