The new API is far from done as the roadmap shows. One point of clarity is that the new Twitch API will not be at feature parity with v3/v5. This is a deliberate decision as we have just over 100 supported endpoints in v3/v5 but 97% of all usage is across 15 endpoints (kind of crazy, huh?). We’re focusing on fewer endpoints that are purposefully designed and provide value to developers.
For the website, we’re well aware that v5 has too much prominence for something that is deprecated. We’re fixing it. 
Hope that helps bring some clarity!