The rules for anime series are a little different. They full guidelines are not yet in the Bible, but you can read the main guidelines here: https://www.themoviedb.org/bible/new_content#5a6a6a919251416d74000001

(I'm just stopping by to share the guidelines. I'll handle the actual report later. )

This series would fall under the alternative timeline part of this guideline:

"Reboot series, spin-off series, series set in an alternative timeline, new adaptations based on the same source material and new prequel series, to only name a few possibilities, are added as a new TV entry."

Good point. But I think it might be an exception because of the theme of the series.

True, it's probably an edge case, but pretty much everywhere else seems to be treating is as a separate series, including TVDB, ANN, IMDB, and Crunchyroll.

MAL lists the Blu-ray special, Steins;Gate: Kyoukaimenjou no Missing Link - Divide By Zero, as an alternative version of the ending of the original series and Steins;Gate 0 as a sequel to specifically that alternative version special.

Yup, yup. I'm looking at it now and anime websites appear to be divided. It might be better as separate entries after all.

I'll wait a bit to see if anyone else has an opinion on whether it's a proper sequel or not.

I tried to get them merged on TVDB (in the general season thread) but was straight up ignored ... It's really a fringe case since it's about an alternate timeline he visits in the main show... so it builds off knowledge people have of said events (a divergent sequel really). The main reason for splitting it off is imho just to allow that show to be truly independent should other content arise.

The main reason for splitting it off is imho just to allow that show to be truly independent should other content arise.

Another good point. I think maybe we should play it safe then, and keep them as two entries.

I agree with everything that said above about keeping them separate but season 2 is still there. Maybe it is re-added?

I think I just never got to it. Thanks for the very necessary bump, @brkge !