I never said the position was easy to play for either color. Seems like Batsiashvili didn't find the correct defensive plan with Kg7 and Rh8 after 14.Qh5.

However, I am claiming that 5...Bb4 might be equal instead of slightly better for White which was believed a long time.

One of the main issues for Black in the Vienna was this line where White generates a very strong attack for the cost of 1 pawn:
1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 dxc4 5. e4 Bb4 6. Bxc4 Nxe4 7. O-O Nxc3 8. bxc3

Most Black players here are playing 8...Be7 to avoid 9.Ng5 but my idea is to let White play it. So we enter this line which is most commonly played here:
8...Bd6 9. Ng5 h6 10. Qh5 O-O 11. Ne4

Now it is considered that 11...f5 is the only reasonable continuation after which White gets a strong bind for the cost of 1 pawn.

My suggestion is 11...Nd7! after which SF17 claims 12.Bxh6 is already better for White (+0.68). But Stockfish is wrong 
Stockfish cannot calculate far enough:
1. d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 dxc4 5. e4 Bb4 6. Bxc4 Nxe4 7. O-O Nxc3 8. bxc3 Bd6 9. Ng5 h6 10. Qh5 O-O 11. Ne4 Nd7 12. Bxh6 gxh6 13. Qxh6 Re8 14. Rad1 Bf8 15. Qf4 Bg7 16. Rd3 Nf8 17. Rg3 Ng6 18.Qg4 Bf6

And here White can either take the repetition of moves with 19.Rf3 Bg7 or continue the attack with 19.f4. But once we reached this position (which is following the top engine line by the way), SF17 seems to agree that there is nothing for White. I'd argue that most White players probably would try to win this position as they believe they are better here (because SF claims 12.Bxh6 is better for White) and even lose this position because they are a piece down. I believe that's also the reason why most Black players are playing 11...f5, simply because they didn't look far enough into that Bxh6 sacrifice. All in all, I think this is a good fighting chance for Black.