E2: Meta Threads is a big marketing opportunity now, but it will not last.
Meta will not combine Threads with Instagram, like they say they will.
Instead, Threads is Meta's attempt at making a browser for Twitter-style content. This content will be on a public protocol, like ActivityPub. Having a browser for this content will allow Meta to own users' followers and control content.
This is Meta betting on the "Fediverse" and it goes well with their emphasis on the Metaverse. However, I predict the current hype will not last and people will soon grow bored with Threads.