Six and a half paragraphs into the rant, and I think I found the argument:
“every mute and block is now treated, per Musk, as a ‘downvote’ of that account, and there is virtually no degree of positive engagement that can counterbalance a mass muting or blocking or false-reporting campaign. But the worst part is this: the ‘disappeared’ account-holder may take months to realize that they have been made virtually invisible on Twitter, or may never even find out at all.”
Unmentioned and uncited is the actual policy change: you can now pay for a downvoting account [1].
[1] https://mobile.twitter.com/elonmusk/status/16039854915057950...