I think they are covering their tracks and removing the bans, shadow bans, and censorship before Musk takes over and revealed it.
More likely that the bot farms decided to go into overdrive while no one is at the wheel. Cyber warfare is an arms race, and one side just skipped a turn.
If they purge the code that says "underreport Ted Cruz's follower count by 10,000", then Ted Cruz's follower count will go up by 10,000 overnight, but they'll have plausible deniability that it naturally happened due to a bunch of conservatives deciding to join Twitter because Elon bought it.
But if they don't purge the code that says "underreport Ted Cruz's follower count by 10,000", then there will be nothing noticeable at first, but then they won't have plausible deniability once that code does eventually get found.
Seriously though, it's incredibly disheartening to see so many people fall victim to rampant misinformation. It's like everyone completely forgot the basic scientific method from middle school, and instead flock around unfalsifiable, sensationalist conspiracies. They're much more interesting, I'll admit, but that's what fiction is for. We live in a demon haunted world.
Maybe Twitter has started enforcing these rules universally, banned some accounts, which affected these numbers?
What seems more likely to me is left leaning people leaving the platform and right leaving people returning to it due to a perceived impending shift in the platforms policies and culture owing to the political views of the new owner.
It’s believable they dislike the change and leaving Twitter. I don’t believe thousands of them have actually deleted their accounts.
People are generally lazy. In my experience, this quality is universal, and applies to 100% of political spectrum. Closing an account takes quite a few clicks.
It’s much easier to stop using Twitter, and uninstall the mobile apps. Doing so doesn’t affect these numbers, at least not until the 6 months specified in the Twitter's “inactive account policy” document.