It's meant to be a decentralised version of Twitter. I think it was originally made by Twitter but is now a separate company.
But I don't think it uses the ActivityPub protocol that Lemmy, Kbin, and Mastodon use, so it won't be interoperable with them. Also, it's invite-only for the moment. So if you want a decentralised Twitter-like experience right now, you could use Mastodon.
No user of Reddit is powerless. Every single user of Reddit has the power to fuck with Reddit in whatever legal way they want, and they also they have the power to quit using Reddit.