Clearly you must know that 1997 never existed and the attitude era started in 1998.
Btw WCW 96, 97 >
For me the Attitude Era started from King of the Ring 1996
I had a really hard time to decide between 97, 98 and 99
2000 was a really great and entertaining year but it was not so much dark, edgy, chaotic (in a positive way) and controversial. It had still some extreme moments or segments (Cactus jack vs. Triple H for example) but it was more funny and colourful compared to WWE 1999.
WWE from the late 1996 to the summer of 1999 was how real wrestlingshows should be. Even if you watched a match between a undercarder vs. a jobber you never knew what would happen in this match, if somebody important would interrupt or if the match would be interrupted to show something backstage.
Find on YouTube some videos from the channel PreShowHeats. The Sunday Night Heat shows were more exiting than the current Raw shows.
It was really tough to decide between 97, 98 and 99 but I voted for 99 because Russo was even more creative and controversial in this year thean 2½ years before with his booking.
WWF Attitude Era at its finest