The party will not accept anyone that doesn't completely conform to the party's policies and ideology, and they perform extensive testing to ensure it.
Obviously.
Just like any other party in the world.
Or do you farking think you can join the CSU and stay there and make a career if you are not a Christian?
Or join the FDP if you are not a liberal?
Or join "die Linke" if you are not a left leaning "socialist"?
What do you think a party is for?
That's it. It doesn't impact what jobs you can get, That is nonsense.
it doesn't change how your vote is counted, Same in China. The vote counts the same.
it doesn't give you more or less say in public policy,
Same in China. And more important: money does not give you power. That is what China was/is scared about: that politics is run by money.
it doesn't change how you participate in life generally, If you believe that about USA: you are an idiot.
No idea why you google for silly links, instead of simply reading the English translation of the party Charta.
In China you join the party, because you want to have a say in politics. Just like you do in other countries. In China the CPC is the parliament. Every decision is done there. If you want to vote about it: you need to be a member. The real "parliament" is only an organ to do the work (and voting) about the exact words of a law.
The people in the party vote on what law they want, e.g. that abortion is legal. The parliament sets up the framework, under what rules is it legal, e.g. till what month of pregnancy. Yeah, the parliament can not make it illegal: because it has to follow the vote in the party. But: it is the organ that describes the rules, and the members vote on those rules.
You should start learning that different countries have different ideas what "democracy" is - and now it is supposed to work.
Your democracy does not work at all since the death Kennedy! Which what audacity do you dare to criticize another country's democracy?