This threat is interesting. I wonder what the minimum number is of top Twitter accounts that would have to leave for the platform to lose an unrecoverable amount of its daily impressions.
For example, out of the top 100 twitter accounts (https://socialblade.com/twitter/top/100), almost all are musicians, sports figures, politicians or news outlets.
If the top 5 musicians and the top 5 sports figures got together and started posting content exclusively on a new platform, I wonder if it would be enough to cause a gravitational shift.