I was an actual computer programmer/analyst in a past life. I've been on Twatter since October 2016.
I'm here to tell you that they've "jacked" [pardon the pun] their software up so much that they probably don't even know what it's doing half the time.
The reason for this is what you're describing in your thread - they're shadowbanning and controlling the speech of those they don't like [mostly on the Right].
I have nicknames for some of their obviously broken pieces. Did you know there was a time for a couple of months when you could "like" a tweet 5,6,7 times? This particular glitch comes and goes. It's related to them trying to prevent "liking" and "retweeting" and making it look like a random software bug.
It's not, because it's replicable.
Another one is "deadheading" [taken from diverting a railroad car into a siding off the main line] - your tweet goes into a "siding" and only a few people can see it - or no one but you can see it.
It's interesting to explore the behavior of those kind of tweets.