
Trakt Representative on their Forums claims API access being restricted to non-VIPs is just a temporary measure
https://forums.trakt.tv/t/failure-to-register-an-api/116157/15
Note that the image above are two images clipped together. This reply was later down in the chain of comments, but is referring to the issue.
I don't know how long this restriction will last but I hope it does end. This is the last straw for me since I don't wish to manually mark everything as watched from Plex.