Chinese Communist Party has not been a left-wing party for a long time. It is an anti-democratic strong government law-and-order nationalist party with fairly extreme pro-business and anti-social-net policies in economics - a mixture that in most countries we know of would be, if anything, far right. Why would any left-wingers support it?
I think your view of party policy is pretty....skewed. To call their policy far-right is just wrong. But you are right in saying that most left-wingers are very Sinophobic these days. It's sad.
And honestly, even if the Communist Party was "far-right", I would still support them. There's been a few hickups along the way, but what they've done for my people has been nothing short of incredible. When my ancestors left China, it was an impoverished, feudal hellhole and one of the most backwards countries in Eurasia. Now they're an emerging superpower and one of the wealthiest countries in the world. I'm not exaggerating when I say I cried while watching the military parade a few months ago. I love China, I love the Party, and I love how proud they make me feel.
