Prepare the filling: In a mixing bowl, beat the softened cream cheese until smooth. Add the sweetened condensed milk, pineapple juice, rum (if using), and vanilla extract, and beat until fully combined and smooth.

1. Whip the cream: In a separate bowl, beat the heavy whipping cream with powdered sugar until stiff peaks form, about 3-4 minutes using an electric mixer.
2. Combine the filling and whipped cream: Gently fold the whipped cream into the cream cheese mixture, being careful not to deflate the whipped cream. Stir in the shredded coconut until evenly distributed.
3. Assemble the pie: Spoon the pina colada filling into the prepared graham cracker crust. Spread the filling evenly and smooth the top with a spatula.
4. Chill the pie: Refrigerate the pie for at least 4 hours or until the filling has set and the pie is firm.
5. Garnish and serve: Once set, garnish the pie with pineapple chunks and toasted coconut, if desired. Slice and enjoy!