from day one you can see the people you've followed. Just go to your profile and click "following".

As for the general implementation, I'm with you on the problems of lacking a feed with only posts from those you follow. But according to the Threads team, this was a minimally-viable-product and features like that are coming soon.

Other than that, it's been very smooth in my experience. And much less full of crap that Twitter. Though that's likely due to it being brand new.