This is why I said you can't always trust Ferrari's claimed figures. By the way, even though this is without rollout, this is the equivalent to 5.6-5.7 in an American mag test, but even then you'll have to compute for a heavier, American-spec model (so, 5.8 it is). That's the same as a Huracan LP610-4 (which posted 5.7 in Car & Driver).
Lamborghini is upper-class Porsche, while Ferrari is a company of its own. The Huracan LP610-4 should make the same awhp as claimed bhp, while the 488 GTB should make maybe a bit less than 600 rwhp. Consider this, the 488 GTB is barely lighter.
The 488 GTB likely has a 10% drivetrain loss, which is surprisingly better than what I expected from Ferrari.