It might not be a popular opinion, but I don't think there should be a mandatory handshake line. The winner won and the loser lost. Having a handshake line directly after the game just provides an opportunity for confrontation. Also, provides an easy target for someone who wants a confrontation.
If players want to congratulate each other, then go ahead, but there should not be an expectation that everyone should do this.
Has an athlete ever said, "I was gonna fight them, but they shook my hand in the line, so I decided against it".
It's just a forced formality with no purpose, outside of giving those that want issues a place to have issues.