Source of this is from Matthew Prince, Co-founder & CEO of Cloudflare posted at 11:34 Jul 9,2023. It was posted to his twitter (@eastdakota). Not linking to twitter bc don't want a deadlink next time twitter makes API changes. And not to drive traffic to twitter :D
Edit:
July 11th update, arstechnica published a detailed explanation
While I would love to see Twitter auguring straight into the ground, Twitter’s API changes would explain some portion of this traffic changes. I wonder if there are any other proxy measures for audience engagement as separate from basic traffic