The fact that moderation tools exist does not imply that they are being used for political censorship. None of the screenshots of "search blacklisted" accounts from the leak showed any evidence of it being used on actual people, they are all random alphanumeric usernames with more reports than tweets.
In fact, the opposite is true. In 2018, when the feature was first rolled out, it was found to be catching several notable conservative commentators because their tweeting behavior is hard to distinguish from trolls and spambots (wonder why...), so those people were explicitly whitelisted so that they would appear in searches and trends despite their bad behavior.
There’s no goalpost moving here - a social media site having the ability to prevent large volumes of spam making its way to the trending page in front of thousands of eyeballs shouldn’t come as a surprise to anyone. The number of crypto scams in replies to tweets by Elon himself suggests that this tooling is definitely not as draconian in ability as you seem to believe.
Your email provider also has “secret” blacklists, and if incoming email originates from a sender on those lists then it gets put in your junk (or even bounced). Does that concern you?
I think this is what I don’t understand about the general sentiment that Twitter is some kind of uber-censored platform. Sure, high profile accounts and tweets can sometimes be removed, but have you ever tried reporting tweets?
9 out of 10 times that I report tweets threatening violence or harm against someone, I get a notification a few hours later that the “moderation team” has reviewed that tweet and found it not to be in breach of any policies. Twitter’s reporting system is ineffective at best, and I almost wish I had seen the kind of heavy handed moderation that people prescribe to Twitter here.