But he is overlooking some defensive resources. Black should play 19...Be6 20.Qe2 Nc7 21.Nxc7 Qxc7 22.Nd3 Bf7 23.Bxf7+ Qxf7 24.Nxc5 Qc7 25.Ne6 Qxh2 26.f4 Re8 with a good game.
In the other line for White that Monokroussos recommends 7.Nxd4 Qe7+ 8.Be2 h6 9.Ngf3 c6 10.O-O Qf6 11.Re1 Bb4 12.c3 Bd6 13.Ba6+ Kf7 14.Bd3 Ne7 15.c4, I prefer to defend by 15...Rf8 16.Bd2 Kg8 17.Bc3 Qf7.
And if White goes for mating threats with 18.Bc2 Na6 19.cxd5 Nxd5 20.Qd3, then 20...g5 21.Ne5 Bxe5 22.Rxe5 Nab4 is a satisfactory response.