Play the King's gambit and you can avoid a lot of defenses Black has. It's more fun too.
Is Kramnik's "Berlin Wall" the end of 1.e4?
I just checked ECO Volume "C" 5th edition a few minutes ago and noticed Shirov has played the Spanish 4 Knights Opening quite a bit and obtained excellent positions.Also Kramnik and Spassky have done this.It all boils down to who understands the plans and objectives best in the positions reached.

The "Berlin Wall" will probably never be refuted.There are currently several volumes of theory after each of whites or blacks moves.
I believe whites best try may be to simply transpose into a Spanish 4 Knights game, which has not been analyzed as deeply as the Ruy Lopez and may still offer white chances for an initiative that lasts.
The book by Cox and the Chess Stars one are about the only materials you'll need on the Berlin. That and maybe a database for studying Berlin Wall games.

Play the King's gambit and you can avoid a lot of defenses Black has. It's more fun too.
The problem is black can force an advantage if he knows how.

Fischers defense is full of holes, look at recent master games, ever wonder why the modern defense is favored at top level
Dear Arkhemeedes: After 5.g3? g4! 6.Nh4 f3 7.Nc3 Bg7 or if 7.h3 h5! and white has nothing.If instead of 6.Nh4 white plays 6.Ng1 f3! 7.h3 Qf6! threatening 8...f2.A really great defence against the Kings Gambit however is 3.Nf3 h5!? 4.d4 g5 5.Bc4 g4 6.Ne5 Qh4 7.Ke2 f3.

Lol whit actually wouldn't play h4 Bc4 followed by gx Qx and I assume Bg7 and white 0-0
But after g5 instead of g3 Bc4 is good enough for an advantage

1. e4e52. f4exf43. Nf3d6(3... h5!?4. d4g55. h4g46. Ne5d67. Nd3f38. Bf4fxg2(8... Be79. Bg3d510. gxf3)9. Bxg2Bg710. c3Nf611. O-Oor (11. Nd2followed by queen side castling )11... c612. Nd2Be613. Qe1and White has more than enough for the pawn )4. d4g55. g3g46. Nh4f37. Nc3Bg78. Be3Ne7(8... Nc69. Qd2Nce710. O-O-Oc6Blacks setup is passive but he is at least coverning some important central squares 11. Bd3(11. h3!?)(11. Kb1!?)11... Qa512. Rhe1b513. Nf5Bxf514. exf5O-O-O15. Bg5b416. Ne4)(8... c69. Qd2Ne710. O-O-Od511. h3!)(8... Nf69. Qd2d510. e5Ne411. Nxe4dxe412. O-O-O)9. Qd2Ng610. Nf5And nor for example
(10. O-O-O)10... Bxf511. exf5Ne712. Bg5f613. Bh6Nxf514. Bxg7Qe7+15. Kf2Qxg716. Re1+Kd817. Nd5Nc618. Nf4Kc819. Ne6Qh620. Qxh6(20. Qc3!?could also be played )20... Nxh621. c3Kd722. Nf4Ne723. h3
Dear Arkhimeedes: You are correct about 3.Nf3 h5 but let us examine again 3.Nf3 d6 4.d4 g5 5.g3?! g4 6.Nh4 f3 7.Nc3 at this point 7...Bg7 is a book move which is not blacks best.Houdini 4 likes 7...Be7! 8.Nf5 Bf5 9.ef5 Bf6 10.h3 h5 11.Nd5 Bg7 and white has nothing.If after 7...Be7 8.Be3 Bh4 9.gh4 Qh4 10.Bf2 Qg5! and once again white has nothing.
Dear Arkhimedes: Please consider this as a footnote to the above post concerning 3.Nf3 h5 4.d4 g5 5.h4 g4 6.Ne5 d6 7.Nd3 f3 8.Bf4 Nc6! (instead of 8...fg2)9.d5 fg2 10.Bg2 Nce7 11.Bg3 Ng6 and black is fine. The moves that players of the white pieces seem to hate most however are 3.Nf3 Be7 4.Bc4 Bh4 5.Kf1 and 2.f4 d5 3.ed5 c6 both of which give white
nothing.
When I play the Berlin Wall and encounter 4.d3 I usually go, "Aww, come on I wanna get queens off the board!" =(

When I play the Berlin Wall and encounter 4.d3 I usually go, "Aww, come on I wanna get queens off the board!" =(
Being that I am a positional player normally and like to keep my material, I'd likely only disappoint you also...
Hmm. Why should drawing against an defense (at least) be the end of e4? Not many players have such resources or that kind of talent to play such an defense with tenacity to just draw. Meaning, an practical way, e4 remains one of two of the strongest openings in chessdom.