Also now white has a dominate position in the center. After 4. f3xd4 c6xd4 5. Queen x d4 should black now venture 5.knightf6 white plays 6.e5 gaining a tempo. Should black play 5.d6 white still plays 6.e5 hoping black will play 6. d6 xe5. White then goes for a queen exchange. Black must take back with king then whites bishop to c4 puts immediate pressure on the undefended f7 pawn.
The Beauty of the Scotch Game

To drive home my point it is blacks naive c6xd4 that makes all of this possible. But even if black doesn't play c6xd4 and plays Bc5 it is still I believe a very active position for White.

4...Nxd4 is a TERRIBLE move. In addition yo 4...Bc5, Black can also play 4...Nf6. One is no better than the other. Matter of taste and preference by Black.
But what's even better? Avoiding the Scotch all together! And I have seen some try to mix the move order, not a problem for Black.
Avoiding the Scotch:
1.e4 e5 2.Nf3 Nf6!
1.e4 e5 2.d4 exd4 3.Nf3 Bb4+! 4.c3 dxc3 5.bxc3 Be7 and Black is a pawn up!

No my friend nf6 allows white to play e5! skedaddling the black knight away I covered that variation in my original post play nf6 and I'll be happy
The Scotch Game is a natural game for aggressively inclined players. After 1. e4 e5 2. nf3 nc6 3. d4 e5xd4 4. f3xd4 c6 x d4 This particular variation in the Scotch Game is a wonderland of possibilities for White. c6 x d4 is a bad move but it seems so natural many play . Better for black would be 4. Bc5 for example. The beauty of this opening for White is that black blesses him like Buddha with 4.c6 x d4. It looks like such a natural move but it is bad no matter which way you look at it as black