g3 goesn't make much sense, Black is comforably equal after his ...Nxd4.

7.de5 Ne3 8.Qh3 is well analysed to an endgame where Black does not have enough for the pawn.

Factly, 0-0 may be more accurate than Qf3, although the "mainline" is the same after ...Bb7.There is a good point, though:

After 10.0-0 Black may replace 10...Bb7 with 10...ed4, but he is worse after 11.Bc6 Rb8 12.d3 Nf4 13.Na3!.

After 10.Qf3 there is the long, practically forced line 10...ed4 11.Bc6 Nb4 12.Bxa8 Nc2+ 13.Kd1 Bg4 14.Kxc2 Qc5+ 15.Qd1 Bxf3+ 16.Bxf3 d3, given in the old Zagorovski "Romantic Chess Openings" book as better for Black. Factly, I have won with it as Black against a Greek master some thirty-two years ago, but objectively speaking this is just equal, and it's Black the one that has to be careful.

12.0-0 Bb7 (better is Rb8, still inadequate) 13.Re1 is winning for white (Fischer played 13.d3? which loses to 13...Bxh2+ but that last move wasn't played).

12.h4 is also strong.