Wouldn't be good for protestors. Wouldn't be good for anarchists. Wouldn't be good for people using someone else's ID for transit. If you're on this site, chances are you wouldn't be getting tax breaks for community service; you'd be getting blacklisted from trains for jaywalking or missing a dinner reservation. Like fuck, I'd consider myself a Tankie, but I don't see an upside remotely worth the cost of this.
Not to mention the surveillance required to make social credit viable. 'Actual credit in America is even worse!' is a bullshit argument too.
So from what I understand ~200-300 people died in Tiananmen Square in 1989, right? Like, that's not ideal, but also not 3000 people. Still, I generally subscribe to the "murder is bad" school of thought.