1. All this achieves is two separate unchallenged echo chambers.
2. If your going cite Hannah Arendt then know one of the properties of the “public sphere” is spatial meaning the activities are located in a public space where people are able to meet one another for discourse.
I reject the core idea of twitter, bluesky or whatever comes after. Text is not a good medium. Anonymity behind a keyboard and an avatar is a playground for bad actors.