I'd be the last person to downplay the fact that the Bluesky app has a serious retention problem. But it has "broken through" in an incredible way and DAUs/MAUs are quite stable.
Registered users is not at all meaningless. Bluesky has those user's email addresses, the mobile app is still installed on many of their devices, they have accounts, and they can potentially be reactivated.
For example, if Bluesky announced a feature exciting enough, like subcommunities, it could email those 50M users and possibly bootstrap a serious open network competitor to Reddit.
Based on your comments, it seems like you're trying to spread FUD?
The stats page you linked to explains exactly what's going on. These spam PLC identities have nothing to do with with the tens of millions of real Bluesky registered users.
Either you misunderstood or you're being intentionally dishonest.
You still seem to be implying the number of real registered users on Bluesky isn't ~50M, which it is. The PLC identity spam you referenced is not being counted in this number.
It is confusing to say "users" when it is actually "accounts", humans tend to associate "user" with another human, where as "account" can cover people and bots (many on atproto)
Of course investors care about registered users, for the same reason I explained. But yeah, they do care a lot more about retention and growth rate for good reason. Bluesky Social, PBC has raised $120M+ dollars from investors.
Registered users is not at all meaningless. Bluesky has those user's email addresses, the mobile app is still installed on many of their devices, they have accounts, and they can potentially be reactivated.
For example, if Bluesky announced a feature exciting enough, like subcommunities, it could email those 50M users and possibly bootstrap a serious open network competitor to Reddit.