Using an ice cream scoop, remove three large scoops ice cream to a plate. Place the plate in the freezer and return the gallon to the freezer.
Add 9 of the waffle cones to the bowl of a food processor. Pulse until the cones become a mix of mostly crumbs with a few larger chunks here and there. Pulse in the melted butter until well combined. Press the mixture into the bottom of a 9-inch nonstick springform pan. Bake for 5 minutes. Let cool completely, about 10 minutes.
Remove the rest of the ice cream from the freezer to start to soften it a little bit.
Meanwhile, put the white chocolate and coconut oil in a microwave-safe bowl. Microwave in 15-second increments until melted and smooth. (This time will vary based on your microwave.) Working one at a time, dip the top quarter of the 3 remaining waffle cones in the white chocolate mixture, then sprinkle with about 2 tablespoons rainbow sprinkles. Place the cones onto champagne flutes, decorated-side down, to set. (You can also set them on wax paper to set.)
Add the remaining softened ice cream to the crust and spread to smooth. Sprinkle the chopped strawberries over the top and gently press into the ice cream. Using a spoon, drizzle the top with the remaining white chocolate mixture. Finish with the remaining tablespoon sprinkles.
Remove the scoops of ice cream from the freezer and place them in the center of the pie. Top each scoop with one inverted decorated ice cream cone; be sure to place them on an angle, so they are not sitting vertically on the ice cream scoops. Transfer the pie to the freezer and let set for at least 2 hours.
When ready to serve, run a sharp knife around the edge of the pie to help release it from the springform pan. Remove the pie from the pan, slice and serve drizzled with the strawberry sauce.