The Bluesky infra would not be able to handle scale without invite-only clownshow. Meta can open the floodgates without breaking a sweat.
Honest question: are they emulating "classical Twitter" to the extent of going with self-hosted inefficient Rails implementation? Or what is their problem with scaling exactly in 2023 beyond ordering more instances in some AWS gui?
Is it any surprise Facebook got this right? Understanding "it's cool because there are people there" is part of their origin story, after all.
Protocol: https://atproto.com/
All Bluesky posts in real time: https://firesky.tv/
The threads app can pull in millions in a day because they can login with Instagram SSO, zero friction.