Bullcrap. The Viper is faster. Only things holding it back are top speed (due to aero) and quartermile acceleration (due to traditional manual transmission).
Also, Ferrari doesn't underrate horsepower figures for most of its cars so the Viper would beat that 488 GTB's trap speed in the quartermile if it had a dual-clutch and regular package (assuming the curb weight remains identical).
Also, Viper is not even a 488/Huracan/Z06 competitor. It's an upper-scale supercar like the 812, Aventador, Ford GT.
McLaren created the 675LT in response to the Viper ACR for a reason. And the Aventador SV was created in response to the 675LT. All three of them were much faster than a 458 Speciale on a track, let alone the comfort-oriented 488 GTB. (458 Speciale is a GT-R NISMO competitor.)