Public voting data isn't always a good thing.

On one hand, it makes representatives accountable to the public, which is good. On the other, it heavily encourages voting among party lines, and makes lobbying a lot easier (as the lobbyists know whether the representatives voted the way the lobbyists wanted). This effectively moves the heart of government from the representatives themselves to lobbyists and high-level party officials.

It's a bad idea in the same way letting you photograph your ballot and upload it to social media is a bad idea; there's a reason most democracies disallow that.