194
Threads already has over 95 million posts, 30 million signups
(www.theverge.com)
This is a most excellent place for technology news and articles.
The barrier to entry is extremely low. If you have Instagram on your phone, you can just download the app and sign in using the same saved credentials, so you don't even have to create a new account or type in your password.
Given that, and the very large pent-up demand for a decent alternative to Twitter, I'm not at all surprised it's doing well.