To me, this crosses a major line. I don't feel I can trust any site Amazon owns going forward. Any accounts I have currently with this (including my preexisting IMDB account) I now plan to delete, and avoid like the plague so I avoid having more accounts created without my consent. I think people need to react very negatively to this, as it sets a horrible precedent. Imagine every site that currently pops up with "Sign-in with Google" just taking it upon themselves to proactively create an account for simply visiting the page.
I found this help article that explains they're doing it. This doesn't make it better, it just shows it isn't a mistake. Someone made this decision, it was supported internally, and implemented.
https://help.imdb.com/article/imdb/general-information/imdb-...
https://en.wikipedia.org/wiki/Enshittification
https://www.newyorker.com/culture/infinite-scroll/the-age-of... | https://archive.is/Pn0tm