Stir graham crumbs, sugar, and melted butter in a bowl until the mixture feels like damp sand.
Press the crust firmly into a 9-inch pie plate, pushing up the sides. Chill while you make the filling.
Beat softened cream cheese until smooth and fluffy, about 1 minute.
Stream in condensed milk and mix until silky with no lumps.
Whisk in lemonade concentrate, lemon juice, zest, vanilla, and salt until fully combined.
Fold in the whipped topping gently to keep the mixture light and airy.
Scrape filling into the chilled crust and smooth the top. Refrigerate 4–6 hours, or until set.
Slice and serve cold. Garnish with extra whipped cream or lemon slices if you like.