Inertia, there's more content on Twitter still than Threads.

Elon is definitely working to kill the platform with all these random by fiat changes he's making in the name of "free speech" - which to the right means you can lie and spread as many conspiracy theories as you want. I don't think the general population is interested in that - there is a medium of sensible moderation that keeps discourse civil and roots out the worst of the lies and conspiracies.