The characteristic item of legibility is "papers": ID cards, passports, and so on; but also things like title registers. In a transparent rule-of-law society the control systems enabled by these are generally to the public benefit, which is why they get instituted in the first place. But at every stage there's people and situations that don't "fit", and a huge temptation to hammer the square peg into the round hole. Impositions ranging from "no you cannot have the right gender on your passport" to wholesale ethnic cleansing.
And the stuff about the inability to correct mistakes in authoritarianism leading to scientific and technical error is spot-on. That's how the Soviet Union got Lysenkoism, and its space program only survived due to the personal political effectiveness of Korolev (who had already been in a gulag!).